Project 1_Comparative study of different storey buildings for Seismic forces
AIM: Model and analysis of the building from building A to building K as per the data given below in a table and compare the analysis of these buildings on various parameters.
- Factors influencing the dynamic characteristics of a building.
- Factors influencing the Natural Period of a building.
- Factors influencing the Mode shape of oscillations.
PROCEDURE:
- First of all open the software ETABS.
- Below image shows the first interface of the software. Initially this page opens up as we open the ETABS software.
- After opening the software there is a home page where there is an option called New Model just click on that as shown in the below figure:
- After this an another dialouge box opens as we select the option new model.
- A new window named as Model Initialization as shown in the below figure:
- In this dialouge box there are few Initialization options as we can see in the above image and these options are: Use Saved User Default Settings, Use Settings from a model file( we can use this option if we have already worked on some projects then this is the default setting) and the last option is Use Built-in Settings With( and we will be using this option now because this is the first time that we are working for ETABS software).
- As we are going to be working with the third option then after clicking on that option we will be able to see that there are another options in the Use Built-in Settings With, and here are the options:
- Display units : Set it as Metric SI.
- Region for Default Materials : Set this as Indian.
- Steel Selection Datatbase : Set it as Indian.
- Steel Design Code : Set it as IS 800:2007.
- Concrete Design Code : Set it as IS 456:2000.
- Now we are done with the Model Initialization. We have put all the necessary information regarding the modelling as we can see in the below image:
(A) For Building A:
Given Data for Building A:
- Description: 2 Storey building
- Number of storeys 2.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 400X400mm.
- After completing the Model Initialization process another dialouge box appears on the screen named as New Model Quick Template as shown in the below figure:
- First of all we need to create grids according to the plan given in the question. So for creating grids click on the option Custom Grid Spacing. There is another option called Edit Grid Data as shown in the below figure:
- After clicking on the option Edit Grid Data there is another window that opens named as Grid System Data as shown in the below figure:
- Now set the all necessary data in this Grid System Data option. Our X and Y grid sizes are 4 X 4. We have 3 columns and 4 rows that means we have 3 blocks in the Y-direction and 4 blocks in the X-direction.
- Now set the all necessarey data in the given table as shown in the below figure:
- After assigning the grids now we have to assign the number of storys that our building have.
- So in order to do that first we need to go to the option Custom Story Data and then click on the option Edit Story Data as shown in the below figure:
- After this a new dialouge box appears on the screen as we can see in the below given image:
- So now here in this dialouge edit the storys and their heights and other necesseary data.
- So first of all click on the option story 1 in this dialouge box and rename it as Plinth Level and give it a height of 1.5 as mentioned in the above question itself as shown in the below figure:
- And now go to the Story 2 option click there and type Storey 1 and give it a height of 3.
- Similarly click on the option Story 3 and give it of height 3 and rename it as Roof as we can see in the below image:
- Upto now we have set the grids and the number of stories and the basic few changes that will be needed in this modeling.
- Below is the image of how it will look like in the 3-D view and the plan view:
- After this we will be closing the 3-D view window and all the unnecessary viewports in order to focus on the floor plan.
- So after closing the 3-D view we will be going to assing the materials.
- And to assign the material we need to go to the option called DEFINE in the file toolbar as shown in the below image:
- After clicking on the Material Property option there will be another dialouge box opens named as Define Materials.
- From there dialouge box click on the option Add New Material as shown in the below figure:
- After clicking on the Add New Material another diaoluge box opens named as Add New Material Property, in that dialouge box there are few other options. Fill all the necessary details in that options.These options are:
- Region : Select as India.
- Material Type : Select as Concrete.
- Standard : Select as Indian.
- Grade : Select as M30.
- Click OK.
- After clicking OK there is another dialouge box that appears named as Material Property Data as shown in the below figure:
- In this dialouge box fill the necessary data that are required in modelling this building as shown below:
- After this go to the option Design property data and then click on the option Modify/Show Material Property Design Data and then there will be another dialouge box that opens named as Material Property Design Data as shown in the below figure:
- Material Name and Type:
- Material Name : Type M30.
- Material Type : Concrete,Isotropic.
- Grade : M30.
- Design Properties for Concrete Materials:
- Concrete Cube Compressive Strength,fck : 30 MPa.
- Leave the option uncheck on the Lightweight Concrete because it is not a high rise buiding.
- And then click OK.
- Now the concrete material has been added into the list.
- Now we have to add the Rebar for the longitudinal reinforcement.
- So in order to do that first we need to go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 500.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- After this similarly add the rebars for the shear reinforcement, in order to do this process go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 415.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- Now the materials have been added as shown in the below figure:
- Click OK.
- After adding the materials to the plan now we will be adding the beams,column and the slab.
- First of all lets add beam,so In order to do that first do to the Detail option in the file toolbar as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Beam 300X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 300.
- And then click on the option Modify/Show Rebar option.
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option M3 Design Only (Beam).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Cover to Longitudinal Rebar Group Centroid:
- Top Bars : 55 mm.
- Bottom Bars : 55 mm.
- And then Click OK.
- Now click on the option properties Modifier in the Frame Section Property Data window as we can see in the below given image:
- After clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 35%.
- Why do we change MI about 35%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for beams should be 35% as we can see in the below image:
- So here we will change the Moment of Inertia upto 35% as we can see in the below image:
- After this click OK.
- The beams have been added.
- Now we will be adding the columns details.
- In order to add the column details as new element in the frame section, first go to the Define option in the file toolbar at the top of the screen and then go to the Frame section ,as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Column 400X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 400.
as shown in the below figure:
- And then click on the option Modify/Show Rebar option as shown in the below figure:
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option P-M2-M3 Design (Column).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Reinforcement Configuration:
- Check on the Rectangular option.
Confinement Bars:
- Ties.
Check/Design:
- Check on Reinforcement to be designed.
And all the other necessary data require.
- And now click on the option OK.
- Now go to the option Properties modifier at the right hand side of the page.
- And then after clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 70%.
- Why do we change MI about 70%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for columns should be 70% as we can see in the below image:
- So here we will change the Moment of Inertia upto 70% as we can see in the below image:
- Now click the option OK.
- Now we are done with adding the columns and the beams as we can see in the below image:
- After adding the columns and the beams, now we are going to add the slab of 150mm thickness.
- So in order to add the slab,first we need to go to the Define option and then click the option Slab Sections as we can see at the below given image:
- After clicking on the slab sections option a new dialouge box appears on the screen named as Slab Properties and in this there is an option called Add New Property just click on that option as we can see at the below image:
- After clicking on the option Add New Property a new dialouge box opens called Slab Property Data as shown in the below image:
- Fill out all the necessary data.
General data:
- Property Name : Slab 150 mm.
- Slab Material : M30.
- Modelling Type : Membrane
We will not going to check the option Use Special One-Way Load Distribution because here all the slabs are two way slab because the ratio of their length and the breadth is less than 2 ie,
LB=44=1">LB=44=1LB=44=1 which means all the slabs here are two way slab.
Property Data:
- Type : Slab.
- Thickness : 150 mm.
- After filling all the necessary data we will be clicking on the OK option as we can see at the below given image:
- Uptill now we added beams,columns and the slab successfully.
- After this we will be drawing the columns at the plan.
- So in order to create/draw the columns first we need to go to the plan view.
- Here select all storeys at the right bottom of the screen as we can see at the below given image:
- Now to create the columns in a quick way we need to go to the option Quick Draw Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Property : Select Column 400X400.
- Moment Releases : Select Continous.
- And then place the column accordingly. After using the Quick Draw Column option it will become easier to draw the column. This option automatically tells the exact location or the mid-point where we have to put the column in the plan as we can see in the below image:
- Similarly place all the columns in the same way. After placing the columns in the plan the plan will look like in the below given image:
- The columns have been successfully placed at their places.
- We can see the column placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- Now that the columns have been created,now we will be creating beams and these columns are joining with these beams.
- So in order to create beams first go to the plan view and select all story at the right bottom of the screen as we can see at the below given image:
- Now to create the beams in a quick way we need to go to the option Quick Draw Beams/Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Beams/Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Type of Line : Frame.
- Property : Select Beam 300X400.
- Moment Releases : Select Continous.
- And then place the beams accordingly. After using the Quick Draw Beams/Column option it will become easier to draw the beams as we can see in the below image:
- Similarly place all the beams in the same way. After placing the beams in the plan the plan will look like in the below given image:
- The beams have been successfully placed at their places.
- We can see the beam placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- After placing the columns and beams in the plan, now we have to place a slab.
- In order to place a slab in the plan first of all go to the plan view of the model and then go to the option Quick Draw Floor/Wall which is present at the left hand side of the screen as shown in the below figure:
- After clicking on the option Quick Draw Floor/Wall there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Property : Slab 150mm.
- Local Axis : 0.
- Draw Object Using : Grids.
- And then place the slabs accordingly. After using the Quick Draw Floor/Wall option it will become easier to draw the slab just click in the centre of the grid then the slab will be automatically created just as simple as that,we can see in the below image:
- Similarly place all the slabs in the same way. After placing the slabs in the plan the plan will look like in the below given image:
- The slabs have been successfully placed at their places.
- We can see the slab placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- After placing the slab on all the storeys we will be assigning the base of the building as the pinned.
- In order to do that first we need to go to the plan view.
- And for assigning the base of the building we will be working on the base plan.
- And select only one story that is base storey because we have to assign the base.
- Now select all the joining points of the plan as shown in the below figure:
- Now go to the Assign option in the File toolbar then click on the Joint and then click on the Restraints as shown in the below image:
- After clicking on the option Restraints a new dialouge box opens up named as Joint Assignment-Restraints.
- In that dialouge box there are other options in Fast Restraints column just click on the option Pin then select the base as pin as shown in the below image.
- And then click on the option APPLY and then OK.
- Now we will be adding the loads in the plan.
- So in order to add these loads first go to the Define option which is present at the top of the ETABS screen and then click on the option Load Patterns just as shown in the below figure:
- After clicking on the Load Patterns option a new dialouge box opens named as Define Load Patterns just as shown in the below figure:
- Now we have to define the loads in the Loads sections like Loads (Dead load or live load or any other load),the type of load etc just fill this section with the appropriate loadings just as shown in the below figure:
- Now the loads have been assigned accordingly as we can see at the above image.
- Now we have to edit the seismic loads like Eqx,Eqx+,Eqx- etc.
- So in order to do that just click on the option Modify Lateral Load... and then a new dialouge box opens named as Indian IS 1893:2016 Seismic Loading as shown in the below figure:
- First we edit the Eqx load.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx just as shown in the below image:
- Similarly do the same procedure for the Eqx+.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx+ just as shown in the below image:
- For Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx- just as shown in the below image:
- Now similarly the same procedure for the Eqy as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy just as shown in the below image:
- Now similarly the same procedure for the Eqy+ as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy+ just as shown in the below image:
- Now similarly the same procedure for the Eqy- as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy- just as shown in the below image:
- At last click OK as shown in the below figure:
- Now we will be assigning the live loads to this model.
- In order to assign the live loads first we have to keep the storeys as the Similar Story we can find that option at the bottom of the right hand side of screen as we can see in the below given image:
- After keeping the similar stories we need to select the all shells as we can see in the below given image:
- After selecting the shells go to the option Assign at the top of the screen there will be an option called Assign and from that option there will be another option called Shell Loads from there select option Uniform and then clock just as shown in the below figure:
- After clicking the Uniform option from the Assign tab there will be another dialouge box named as Shell Load Assignment-Uniform as we can see in the below given image:
- Fill the all necessary data in this dialouge box.
Load Pattern:
- Load Pattern Name : Live.
Uniform Load:
- Load : 3KN/m2.
- Direction : Gravity.
Options:
- Check on the option Replace Existing Loads.
- And then click on the option Apply and then OK as shown in the below image:
- After assigning the live loads now we will be assigning the loads on the brick wall or infill wall.
- In order to assign the loads on the infill walls.
- First we have to go to the Select tab and then click on the option select and then Object Type which is seen at the upper side of the screen as shown in the below figure: 
- After clicking on the Object Type option a new dialouge box opens named as Select by Object Type here select the option Beams.
- After selecting the option beam just click on the option Select and then Close as shown in the below image:
- By doing this all the beams have been selected just by a single click.
- Afte this go to the Assign tab at the top of the screen and there select option Frame Loads and then option Distributed just as shown in the below figure:
- After selecting the option Distributed another dialouge box appears on the screen named as Frame Load Assignment-Distributed just fill out the all necessary information just as shown in the below figure:
- After that just click on the option Apply and then OK.
- Now the 10 KN/m loads have been applied on all the infill walls as shown in the below image:
- After assigning the loads on the infill mass now we will be assigning the mass source.
- In order to do that go to the Define tab and then click on the option Mass Source as shown in the below figure:
- After clicking on the Mass Source option a new dialouge box appears on the screen from there select option Modify/Show Mass Source.
- After selecting the Modify/Show Mass Source another dialouge box appears named as Mass Source Data as shown in the below image:
- Fill out all the necessary data in this section as shown below in the given image:
- And then click OK.
- After assigning the loads on the infill mass now we will be assigning the load combinations.
- So in order to do that go to the Define tab whic is present at the top of the ETABS screen just click on the Define tab and then click on the another option named load combination just as shown in the below image:
- After clicking on the Load Combination a new dialouge box opens named as Load Combinations.
- And then click on the option Add Default Design Combos as shown in the below image:
- After clicking on the option Add Default Design Combos there will be another dialouge box that opens named as Add Default Design Combinations as shown in the below given figure:
- In that dialouge box just click on the option Concrete Frame Design and check on the Convert to User Combinations (Editable) just as shown in the below figure:
- Now the load combinations already have been created by the software itself we can see the loadings in the below given image:
- Now after assigning the load combinations we will be assigning the diaphgram.
- And in order to do that first we have to go to the option Select which is present at the top of the screen then click on the option Select and then go to the option Object Type and then option Floor just as shown in the below image:
- After clicking on the Object Type there will be another dialouge box named as Select by Object Type as shown in the below image:
- Select the object type as Floor and then click on the option Select ad then Close as shown in the below image:
- Now click on the option Assign and then select Shell and then Diaphgrams as shown in the below figure:
- After clicking on the option Diaphgrams there will be another dialouge box named as Shell Assignment- Diaphragms.
- Click on the option D1 and then click on the option Apply and then OK as shown in the below image:
- After clicking on the option Apply The below is the result:
- And now after assigning the diaphragm now we will be doing Model Check.
- So in order to do the Model Check first we go to the file tab there will be an option called Analyse click on that option after that click on the option Check the model just as shown in the below image:
- After this a new dialouge box appears on the screen named as Check Model.
- In that dialouge box just click on all the other options.
- And then just click OK just as shown in the below image:
- After clicking on the OK option the new window named as Warnings opens up to show any warning jus as shown in the below image:
- Now we will be doing run analysis.
- In order to do the Run analysis just press f5 or there is an option in the Analyse tab as shown in the below image:
- This is how the buildin will look like after the analysis shown in the below image:
(B) For Building B:
Given data for building B:
- Description: Bench-mark 5 Storey building
- Number of storeys 5.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 400X400mm.
- After completing the Model Initialization process another dialouge box appears on the screen named as New Model Quick Template as shown in the below figure:
- First of all we need to create grids according to the plan given in the question. So for creating grids click on the option Custom Grid Spacing. There is another option called Edit Grid Data as shown in the below figure:
- After clicking on the option Edit Grid Data there is another window that opens named as Grid System Data as shown in the below figure:
- Now set the all necessary data in this Grid System Data option. Our X and Y grid sizes are 4 X 4. We have 3 columns and 4 rows that means we have 3 blocks in the Y-direction and 4 blocks in the X-direction.
- Now set the all necessarey data in the given table as shown in the below figure:
- After assigning the grids now we have to assign the number of storys that our building have.
- So in order to do that first we need to go to the option Custom Story Data and then click on the option Edit Story Data as shown in the below figure:
- After this a new dialouge box appears on the screen as we can see in the below given image:
- So now here in this dialouge edit the storys and their heights and other necesseary data.
- So first of all click on the option story 1 in this dialouge box and rename it as Plinth Level and give it a height of 1.5 as mentioned in the above question itself as shown in the below figure:
- And now go to the Story 2 option click there and type Storey 1 and give it a height of 3.
- Similarly click on the option Story 3 and give it of height 3 and rename it as Story 2.
- Now go to the Story 4 and rename it as Story 3.
- Now add the two more stories by right-clicking the arrow at the left hand side of the screen now add 2 more stories and then press OK.
- And then go to the story 5 and rename it as Story 4.
- And lastly go to the last Story that is Story 6 and rename it as Roof as we can see in the below image:
- Upto now we have set the grids and the number of stories and the basic few changes that will be needed in this modeling.
- Below is the image of how it will look like in the 3-D view and the plan view:
- After this we will be closing the 3-D view window and all the unnecessary viewports in order to focus on the floor plan.
- So after closing the 3-D view we will be going to assing the materials.
- And to assign the material we need to go to the option called DEFINE in the file toolbar as shown in the below image:
- After clicking on the Material Property option there will be another dialouge box opens named as Define Materials.
- From there dialouge box click on the option Add New Material as shown in the below figure:
- After clicking on the Add New Material another diaoluge box opens named as Add New Material Property, in that dialouge box there are few other options. Fill all the necessary details in that options.These options are:
- Region : Select as India.
- Material Type : Select as Concrete.
- Standard : Select as Indian.
- Grade : Select as M30.
- Click OK.
- After clicking OK there is another dialouge box that appears named as Material Property Data as shown in the below figure:
- In this dialouge box fill the necessary data that are required in modelling this building as shown below:
- After this go to the option Design property data and then click on the option Modify/Show Material Property Design Data and then there will be another dialouge box that opens named as Material Property Design Data as shown in the below figure:
- Material Name and Type:
- Material Name : Type M30.
- Material Type : Concrete,Isotropic.
- Grade : M30.
- Design Properties for Concrete Materials:
- Concrete Cube Compressive Strength,fck : 30 MPa.
- Leave the option uncheck on the Lightweight Concrete because it is not a high rise buiding.
- And then click OK.
- Now the concrete material has been added into the list.
- Now we have to add the Rebar for the longitudinal reinforcement.
- So in order to do that first we need to go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 500.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- After this similarly add the rebars for the shear reinforcement, in order to do this process go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 415.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- Now the materials have been added as shown in the below figure:
- Click OK.
- After adding the materials to the plan now we will be adding the beams,column and the slab.
- First of all lets add beam,so In order to do that first go to the Define option in the file toolbar as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Beam 300X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 300.
- And then click on the option Modify/Show Rebar option.
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option M3 Design Only (Beam).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Cover to Longitudinal Rebar Group Centroid:
- Top Bars : 55 mm.
- Bottom Bars : 55 mm.
- And then Click OK.
- Now click on the option properties Modifier in the Frame Section Property Data window as we can see in the below given image:
- After clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 35%.
- Why do we change MI about 35%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for beams should be 35% as we can see in the below image:
- So here we will change the Moment of Inertia upto 35% as we can see in the below image:
- After this click OK.
- The beams have been added.
- Now we will be adding the columns details.
- In order to add the column details as new element in the frame section, first go to the Define option in the file toolbar at the top of the screen and then go to the Frame section ,as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Column 400X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 400.
as shown in the below figure:
- And then click on the option Modify/Show Rebar option as shown in the below figure:
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option P-M2-M3 Design (Column).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Reinforcement Configuration:
- Check on the Rectangular option.
Confinement Bars:
- Ties.
Check/Design:
- Check on Reinforcement to be designed.
And all the other necessary data require.
- And now click on the option OK.
- Now go to the option Properties modifier at the right hand side of the page.
- And then after clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 70%.
- Why do we change MI about 70%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for columns should be 70% as we can see in the below image:
- So here we will change the Moment of Inertia upto 70% as we can see in the below image:
- Now click the option OK.
- Now we are done with adding the columns and the beams as we can see in the below image:
- After adding the columns and the beams, now we are going to add the slab of 150mm thickness.
- So in order to add the slab,first we need to go to the Define option and then click the option Slab Sections as we can see at the below given image:
- After clicking on the slab sections option a new dialouge box appears on the screen named as Slab Properties and in this there is an option called Add New Property just click on that option as we can see at the below image:
- After clicking on the option Add New Property a new dialouge box opens called Slab Property Data as shown in the below image:
- Fill out all the necessary data.
General data:
- Property Name : Slab 150 mm.
- Slab Material : M30.
- Modelling Type : Membrane
We will not going to check the option Use Special One-Way Load Distribution because here all the slabs are two way slab because the ratio of their length and the breadth is less than 2 ie,
LB=44=1">LB=44=1LB=44=1 which means all the slabs here are two way slab.
Property Data:
- Type : Slab.
- Thickness : 150 mm.
- After filling all the necessary data we will be clicking on the OK option as we can see at the below given image:
- Uptill now we added beams,columns and the slab successfully.
- After this we will be drawing the columns at the plan.
- So in order to create/draw the columns first we need to go to the plan view.
- Here select all storeys at the right bottom of the screen as we can see at the below given image:
- Now to create the columns in a quick way we need to go to the option Quick Draw Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Property : Select Column 400X400.
- Moment Releases : Select Continous.
- And then place the column accordingly. After using the Quick Draw Column option it will become easier to draw the column. This option automatically tells the exact location or the mid-point where we have to put the column in the plan as we can see in the below image:
- Similarly place all the columns in the same way. After placing the columns in the plan the plan will look like in the below given image:
- The columns have been successfully placed at their places.
- We can see the column placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- Now that the columns have been created,now we will be creating beams and these columns are joining with these beams.
- So in order to create beams first go to the plan view and select all story at the right bottom of the screen as we can see at the below given image:
- Now to create the beams in a quick way we need to go to the option Quick Draw Beams/Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Beams/Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Type of Line : Frame.
- Property : Select Beam 300X400.
- Moment Releases : Select Continous.
- And then place the beams accordingly. After using the Quick Draw Beams/Column option it will become easier to draw the beams as we can see in the below image:
- Similarly place all the beams in the same way. After placing the beams in the plan the plan will look like in the below given image:
- The beams have been successfully placed at their places.
- We can see the beam placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- After placing the columns and beams in the plan, now we have to place a slab.
- In order to place a slab in the plan first of all go to the plan view of the model and then go to the option Quick Draw Floor/Wall which is present at the left hand side of the screen as shown in the below figure:
- After clicking on the option Quick Draw Floor/Wall there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Property : Slab 150mm.
- Local Axis : 0.
- Draw Object Using : Grids.
- And then place the slabs accordingly. After using the Quick Draw Floor/Wall option it will become easier to draw the slab just click in the centre of the grid then the slab will be automatically created just as simple as that,we can see in the below image:
- Similarly place all the slabs in the same way. After placing the slabs in the plan the plan will look like in the below given image:
- The slabs have been successfully placed at their places.
- We can see the slab placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- After placing the slab on all the storeys we will be assigning the base of the building as the pinned.
- In order to do that first we need to go to the plan view.
- And for assigning the base of the building we will be working on the base plan.
- And select only one story that is base storey because we have to assign the base.
- Now select all the joining points of the plan as shown in the below figure:
- Now go to the Assign option in the File toolbar then click on the Joint and then click on the Restraints as shown in the below image:
- After clicking on the option Restraints a new dialouge box opens up named as Joint Assignment-Restraints.
- In that dialouge box there are other options in Fast Restraints column just click on the option Pin then select the base as pin as shown in the below image.
- And then click on the option APPLY and then OK.
- Now we will be adding the loads in the plan.
- So in order to add these loads first go to the Define option which is present at the top of the ETABS screen and then click on the option Load Patterns just as shown in the below figure:
- After clicking on the Load Patterns option a new dialouge box opens named as Define Load Patterns just as shown in the below figure:
- Now we have to define the loads in the Loads sections like Loads (Dead load or live load or any other load),the type of load etc just fill this section with the appropriate loadings just as shown in the below figure:
- Now the loads have been assigned accordingly as we can see at the above image.
- Now we have to edit the seismic loads like Eqx,Eqx+,Eqx- etc.
- So in order to do that just click on the option Modify Lateral Load... and then a new dialouge box opens named as Indian IS 1893:2016 Seismic Loading as shown in the below figure:
- First we edit the Eqx load.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx just as shown in the below image:
- Similarly do the same procedure for the Eqx+.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx+ just as shown in the below image:
- For Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx- just as shown in the below image:
- Now similarly the same procedure for the Eqy as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy just as shown in the below image:
- Now similarly the same procedure for the Eqy+ as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy+ just as shown in the below image:
- Now similarly the same procedure for the Eqy- as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy- just as shown in the below image:
- At last click OK as shown in the below figure:
- Now we will be assigning the live loads to this model.
- In order to assign the live loads first we have to keep the storeys as the Similar Story we can find that option at the bottom of the right hand side of screen as we can see in the below given image:
- After keeping the similar stories we need to select the all shells as we can see in the below given image:
- After selecting the shells go to the option Assign at the top of the screen there will be an option called Assign and from that option there will be another option called Shell Loads from there select option Uniform and then clock just as shown in the below figure:
- After clicking the Uniform option from the Assign tab there will be another dialouge box named as Shell Load Assignment-Uniform as we can see in the below given image:
- Fill the all necessary data in this dialouge box.
Load Pattern:
- Load Pattern Name : Live.
Uniform Load:
- Load : 3KN/m2.
- Direction : Gravity.
Options:
- Check on the option Replace Existing Loads.
- And then click on the option Apply and then OK as shown in the below image:
- After assigning the live loads now we will be assigning the loads on the brick wall or infill wall.
- In order to assign the loads on the infill walls.
- First we have to go to the Select tab and then click on the option select and then Object Type which is seen at the upper side of the screen as shown in the below figure:
- After clicking on the Object Type option a new dialouge box opens named as Select by Object Type here select the option Beams.
- After selecting the option beam just click on the option Select and then Close as shown in the below image:
- By doing this all the beams have been selected just by a single click.
- Afte this go to the Assign tab at the top of the screen and there select option Frame Loads and then option Distributed just as shown in the below figure:
- After selecting the option Distributed another dialouge box appears on the screen named as Frame Load Assignment-Distributed just fill out the all necessary information just as shown in the below figure:
- After that just click on the option Apply and then OK.
- Now the 10 KN/m loads have been applied on all the infill walls as shown in the below image:
- After assigning the loads on the infill mass now we will be assigning the mass source.
- In order to do that go to the Define tab and then click on the option Mass Source as shown in the below figure:
- After clicking on the Mass Source option a new dialouge box appears on the screen from there select option Modify/Show Mass Source.
- After selecting the Modify/Show Mass Source another dialouge box appears named as Mass Source Data as shown in the below image:
- Fill out all the necessary data in this section as shown below in the given image:
- And then click OK.
- After assigning the loads on the infill mass now we will be assigning the load combinations.
- So in order to do that go to the Define tab whic is present at the top of the ETABS screen just click on the Define tab and then click on the another option named load combination just as shown in the below image:
- After clicking on the Load Combination a new dialouge box opens named as Load Combinations.
- And then click on the option Add Default Design Combos as shown in the below image:
- After clicking on the option Add Default Design Combos there will be another dialouge box that opens named as Add Default Design Combinations as shown in the below given figure:
- In that dialouge box just click on the option Concrete Frame Design and check on the Convert to User Combinations (Editable) just as shown in the below figure:
- Now the load combinations already have been created by the software itself we can see the loadings in the below given image:
- Now after assigning the load combinations we will be assigning the diaphgram.
- And in order to do that first we have to go to the option Select which is present at the top of the screen then click on the option Select and then go to the option Object Type and then option Floor just as shown in the below image:
- After clicking on the Object Type there will be another dialouge box named as Select by Object Type as shown in the below image:
- Select the object type as Floor and then click on the option Select ad then Close as shown in the below image:
- Now click on the option Assign and then select Shell and then Diaphgrams as shown in the below figure:
- After clicking on the option Diaphgrams there will be another dialouge box named as Shell Assignment- Diaphragms.
- Click on the option D1 and then click on the option Apply and then OK as shown in the below image:
- After clicking on the option Apply The below is the result:
- And now after assigning the diaphragm now we will be doing Model Check.
- So in order to do the Model Check first we go to the file tab there will be an option called Analyse click on that option after that click on the option Check the model just as shown in the below image:
- After this a new dialouge box appears on the screen named as Check Model.
- In that dialouge box just click on all the other options.
- And then just click OK just as shown in the below image:
- After clicking on the OK option the new window named as Warnings opens up to show any warning jus as shown in the below image:
- Now we will be doing run analysis.
- In order to do the Run analysis just press f5 or there is an option in the Analyse tab as shown in the below image:
- This is how the buildin will look like after the analysis shown in the below image:
(C) For Building C(5 Storey with Columns of dimensions 550X300 oriented along X direction)::
Given Data for Building C:
- Description: Benchmark building with rectangular columns oriented along X-direction Storey building
- Number of storeys 5.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 550X300mm.
- After completing the Model Initialization process another dialouge box appears on the screen named as New Model Quick Template as shown in the below figure:
- First of all we need to create grids according to the plan given in the question. So for creating grids click on the option Custom Grid Spacing. There is another option called Edit Grid Data as shown in the below figure:
- After clicking on the option Edit Grid Data there is another window that opens named as Grid System Data as shown in the below figure:
- Now set the all necessary data in this Grid System Data option. Our X and Y grid sizes are 4 X 4. We have 3 columns and 4 rows that means we have 3 blocks in the Y-direction and 4 blocks in the X-direction.
- Now set the all necessarey data in the given table as shown in the below figure:
- After assigning the grids now we have to assign the number of storys that our building have.
- So in order to do that first we need to go to the option Custom Story Data and then click on the option Edit Story Data as shown in the below figure:
- After this a new dialouge box appears on the screen as we can see in the below given image:
- So now here in this dialouge edit the storys and their heights and other necesseary data.
- So first of all click on the option story 1 in this dialouge box and rename it as Plinth Level and give it a height of 1.5 as mentioned in the above question itself as shown in the below figure:
- And now go to the Story 2 option click there and type Storey 1 and give it a height of 3.
- Similarly click on the option Story 3 and give it of height 3 and rename it as Story 2.
- And click on the option Story 4 and renamas we can see in the below image:
- Upto now we have set the grids and the number of stories and the basic few changes that will be needed in this modeling.
- Below is the image of how it will look like in the 3-D view and the plan view:
- After this we will be closing the 3-D view window and all the unnecessary viewports in order to focus on the floor plan.
- So after closing the 3-D view we will be going to assing the materials.
- And to assign the material we need to go to the option called DEFINE in the file toolbar as shown in the below image:
- After clicking on the Material Property option there will be another dialouge box opens named as Define Materials.
- From there dialouge box click on the option Add New Material as shown in the below figure:
- After clicking on the Add New Material another diaoluge box opens named as Add New Material Property, in that dialouge box there are few other options. Fill all the necessary details in that options.These options are:
- Region : Select as India.
- Material Type : Select as Concrete.
- Standard : Select as Indian.
- Grade : Select as M30.
- Click OK.
- After clicking OK there is another dialouge box that appears named as Material Property Data as shown in the below figure:
- In this dialouge box fill the necessary data that are required in modelling this building as shown below:
- After this go to the option Design property data and then click on the option Modify/Show Material Property Design Data and then there will be another dialouge box that opens named as Material Property Design Data as shown in the below figure:
- Material Name and Type:
- Material Name : Type M30.
- Material Type : Concrete,Isotropic.
- Grade : M30.
- Design Properties for Concrete Materials:
- Concrete Cube Compressive Strength,fck : 30 MPa.
- Leave the option uncheck on the Lightweight Concrete because it is not a high rise buiding.
- And then click OK.
- Now the concrete material has been added into the list.
- Now we have to add the Rebar for the longitudinal reinforcement.
- So in order to do that first we need to go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 500.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- After this similarly add the rebars for the shear reinforcement, in order to do this process go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 415.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- Now the materials have been added as shown in the below figure:
- Click OK.
- After adding the materials to the plan now we will be adding the beams,column and the slab.
- First of all lets add beam,so In order to do that first do to the Detail option in the file toolbar as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Beam 300X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 300.
- And then click on the option Modify/Show Rebar option.
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option M3 Design Only (Beam).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Cover to Longitudinal Rebar Group Centroid:
- Top Bars : 55 mm.
- Bottom Bars : 55 mm.
- And then Click OK.
- Now click on the option properties Modifier in the Frame Section Property Data window as we can see in the below given image:
- After clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 35%.
- Why do we change MI about 35%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for beams should be 35% as we can see in the below image:
- So here we will change the Moment of Inertia upto 35% as we can see in the below image:
- After this click OK.
- The beams have been added.
- Now we will be adding the columns details.
- In order to add the column details as new element in the frame section, first go to the Define option in the file toolbar at the top of the screen and then go to the Frame section ,as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Column 550X300.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 300.
- Width : 550.
as shown in the below figure:
- And then click on the option Modify/Show Rebar option as shown in the below figure:
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option P-M2-M3 Design (Column).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Reinforcement Configuration:
- Check on the Rectangular option.
Confinement Bars:
- Ties.
Check/Design:
- Check on Reinforcement to be designed.
And all the other necessary data require.
- And now click on the option OK.
- Now go to the option Properties modifier at the right hand side of the page.
- And then after clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 70%.
- Why do we change MI about 70%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for columns should be 70% as we can see in the below image:
- So here we will change the Moment of Inertia upto 70% as we can see in the below image:
- Now click the option OK.
- Now we are done with adding the columns and the beams as we can see in the below image:
- After adding the columns and the beams, now we are going to add the slab of 150mm thickness.
- So in order to add the slab,first we need to go to the Define option and then click the option Slab Sections as we can see at the below given image:
- After clicking on the slab sections option a new dialouge box appears on the screen named as Slab Properties and in this there is an option called Add New Property just click on that option as we can see at the below image:
- After clicking on the option Add New Property a new dialouge box opens called Slab Property Data as shown in the below image:
- Fill out all the necessary data.
General data:
- Property Name : Slab 150 mm.
- Slab Material : M30.
- Modelling Type : Membrane
We will not going to check the option Use Special One-Way Load Distribution because here all the slabs are two way slab because the ratio of their length and the breadth is less than 2 ie,
LB=44=1">LB=44=1LB=44=1 which means all the slabs here are two way slab.
Property Data:
- Type : Slab.
- Thickness : 150 mm.
- After filling all the necessary data we will be clicking on the OK option as we can see at the below given image:
- Uptill now we added beams,columns and the slab successfully.
- After this we will be drawing the columns at the plan.
- So in order to create/draw the columns first we need to go to the plan view.
- Here select all storeys at the right bottom of the screen as we can see at the below given image:
- Now to create the columns in a quick way we need to go to the option Quick Draw Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data.
Properties of Object:
- Property : Select Column 400X400.
- Moment Releases : Select Continous.
- And then place the column accordingly. After using the Quick Draw Column option it will become easier to draw the column. This option automatically tells the exact location or the mid-point where we have to put the column in the plan.
- Similarly place all the columns in the same way. After placing the columns in the plan the plan will look like in the below given image:
- The columns have been successfully placed at their places.
- We can see the column placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- Now that the columns have been created,now we will be creating beams and these columns are joining with these beams.
- So in order to create beams first go to the plan view and select all story at the right bottom of the screen as we can see at the below given image:
- Now to create the beams in a quick way we need to go to the option Quick Draw Beams/Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Beams/Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Type of Line : Frame.
- Property : Select Beam 300X400.
- Moment Releases : Select Continous.
- And then place the beams accordingly. After using the Quick Draw Beams/Column option it will become easier to draw the beams.
- Similarly place all the beams in the same way. After placing the beams in the plan the plan will look like in the below given image:
- The beams have been successfully placed at their places.
- We can see the beam placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- After placing the columns and beams in the plan, now we have to place a slab.
- In order to place a slab in the plan first of all go to the plan view of the model and then go to the option Quick Draw Floor/Wall which is present at the left hand side of the screen as shown in the below figure:
- After clicking on the option Quick Draw Floor/Wall there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Property : Slab 150mm.
- Local Axis : 0.
- Draw Object Using : Grids.
- And then place the slabs accordingly. After using the Quick Draw Floor/Wall option it will become easier to draw the slab just click in the centre of the grid then the slab will be automatically created.
- Similarly place all the slabs in the same way. After placing the slabs in the plan the plan will look like in the below given image:
- The slabs have been successfully placed at their places.
- We can see the slab placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- Now that the columns hace been placeed at their respective positions now go to the Assign tab which is present at the top of the screen and from there choose an option called Frame section and then the option Local Axes as we can see in the below image:
- After clicking on the option local axes a new dialoyge box opens named as Frame Assignment- Local Axes as shown in the below image:
- In this dialouge box there is an option called Define Orientation so just click on the option Rotation by Angle and give the 180 degree angle just as shown in the below figure:
- After placing the slab on all the storeys we will be assigning the base of the building as the pinned.
- In order to do that first we need to go to the plan view.
- And for assigning the base of the building we will be working on the base plan.
- And select only one story that is base storey because we have to assign the base.
- Now select all the joining points of the plan as shown in the below figure:
- Now go to the Assign option in the File toolbar then click on the Joint and then click on the Restraints as shown in the below image:
- After clicking on the option Restraints a new dialouge box opens up named as Joint Assignment-Restraints.
- In that dialouge box there are other options in Fast Restraints column just click on the option Pin then select the base as pin as shown in the below image.
- And then click on the option APPLY and then OK.
- Now we will be adding the loads in the plan.
- So in order to add these loads first go to the Define option which is present at the top of the ETABS screen and then click on the option Load Patterns just as shown in the below figure:
- After clicking on the Load Patterns option a new dialouge box opens named as Define Load Patterns just as shown in the below figure:
- Now we have to define the loads in the Loads sections like Loads (Dead load or live load or any other load),the type of load etc just fill this section with the appropriate loadings just as shown in the below figure:
- Now the loads have been assigned accordingly as we can see at the above image.
- Now we have to edit the seismic loads like Eqx,Eqx+,Eqx- etc.
- So in order to do that just click on the option Modify Lateral Load... and then a new dialouge box opens named as Indian IS 1893:2016 Seismic Loading as shown in the below figure:
- First we edit the Eqx load.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx just as shown in the below image:
- Similarly do the same procedure for the Eqx+.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx+ just as shown in the below image:
- For Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx- just as shown in the below image:
- Now similarly the same procedure for the Eqy as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy just as shown in the below image:
- Now similarly the same procedure for the Eqy+ as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy+ just as shown in the below image:
- Now similarly the same procedure for the Eqy- as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy- just as shown in the below image:
- At last click OK as shown in the below figure:
- Now we will be assigning the live loads to this model.
- In order to assign the live loads first we have to keep the storeys as the Similar Story we can find that option at the bottom of the right hand side of screen as we can see in the below given image:
- After keeping the similar stories we need to select the all shells as we can see in the below given image:
- After selecting the shells go to the option Assign at the top of the screen there will be an option called Assign and from that option there will be another option called Shell Loads from there select option Uniform and then clock just as shown in the below figure:
- After clicking the Uniform option from the Assign tab there will be another dialouge box named as Shell Load Assignment-Uniform as we can see in the below given image:
- Fill the all necessary data in this dialouge box.
Load Pattern:
- Load Pattern Name : Live.
Uniform Load:
- Load : 1.5KN/m2.
- Direction : Gravity.
Options:
- Check on the option Replace Existing Loads.
- And then click on the option Apply and then OK as shown in the below image:
- After assigning the live loads now we will be assigning the loads on the brick wall or infill wall.
- In order to assign the loads on the infill walls.
- First we have to go to the Select tab and then click on the option select and then Object Type which is seen at the upper side of the screen as shown in the below figure:
- After clicking on the Object Type option a new dialouge box opens named as Select by Object Type here select the option Beams.
- After selecting the option beam just click on the option Select and then Close as shown in the below image:
- By doing this all the beams have been selected just by a single click.
- Afte this go to the Assign tab at the top of the screen and there select option Frame Loads and then option Distributed just as shown in the below figure:
- After selecting the option Distributed another dialouge box appears on the screen named as Frame Load Assignment-Distributed just fill out the all necessary information just as shown in the below figure:
- After that just click on the option Apply and then OK.
- Now the 10 KN/m loads have been applied on all the infill walls as shown in the below image:
- After assigning the loads on the infill mass now we will be assigning the mass source.
- In order to do that go to the Define tab and then click on the option Mass Source as shown in the below figure:
- After clicking on the Mass Source option a new dialouge box appears on the screen from there select option Modify/Show Mass Source.
- After selecting the Modify/Show Mass Source another dialouge box appears named as Mass Source Data as shown in the below image:
- Fill out all the necessary data in this section as shown below in the given image:
- And then click OK.
- After assigning the loads on the infill mass now we will be assigning the load combinations.
- So in order to do that go to the Define tab whic is present at the top of the ETABS screen just click on the Define tab and then click on the another option named load combination just as shown in the below image:
- After clicking on the Load Combination a new dialouge box opens named as Load Combinations.
- And then click on the option Add Default Design Combos as shown in the below image:
- After clicking on the option Add Default Design Combos there will be another dialouge box that opens named as Add Default Design Combinations as shown in the below given figure:
- In that dialouge box just click on the option Concrete Frame Design and check on the Convert to User Combinations (Editable) just as shown in the below figure:
- Now the load combinations already have been created by the software itself we can see the loadings in the below given image:
- Now after assigning the load combinations we will be assigning the diaphgram.
- And in order to do that first we have to go to the option Select which is present at the top of the screen then click on the option Select and then go to the option Object Type and then option Floor just as shown in the below image:
- After clicking on the Object Type there will be another dialouge box named as Select by Object Type as shown in the below image:
- Select the object type as Floor and then click on the option Select ad then Close as shown in the below image:
- Now click on the option Assign and then select Shell and then Diaphgrams as shown in the below figure:
- After clicking on the option Diaphgrams there will be another dialouge box named as Shell Assignment- Diaphragms.
- Click on the option D1 and then click on the option Apply and then OK as shown in the below image:
- After clicking on the option Apply The below is the result:
- And now after assigning the diaphragm now we will be doing Model Check.
- So in order to do the Model Check first we go to the file tab there will be an option called Analyse click on that option after that click on the option Check the model just as shown in the below image:
- After this a new dialouge box appears on the screen named as Check Model.
- In that dialouge box just click on all the other options.
- And then just click OK just as shown in the below image:
- After clicking on the OK option the new window named as Warnings opens up to show any warning jus as shown in the below image:
- Now we will be doing run analysis.
- In order to do the Run analysis just press f5 or there is an option in the Analyse tab as shown in the below image:
- This is how the buildin will look like after the analysis shown in the below image:
(D) For Building D(5 Storey with Columns of dimensions 300X550 oriented along Y direction)::
Given Data for Building D:
- Description: Benchmark building with rectangular columns oriented along Y-direction.
- Number of storeys 5.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 300X550mm.
- After completing the Model Initialization process another dialouge box appears on the screen named as New Model Quick Template as shown in the below figure:
- First of all we need to create grids according to the plan given in the question. So for creating grids click on the option Custom Grid Spacing. There is another option called Edit Grid Data as shown in the below figure:
- After clicking on the option Edit Grid Data there is another window that opens named as Grid System Data as shown in the below figure:
- Now set the all necessary data in this Grid System Data option. Our X and Y grid sizes are 4 X 4. We have 3 columns and 4 rows that means we have 3 blocks in the Y-direction and 4 blocks in the X-direction.
- Now set the all necessarey data in the given table as shown in the below figure:
- After assigning the grids now we have to assign the number of storys that our building have.
- So in order to do that first we need to go to the option Custom Story Data and then click on the option Edit Story Data as shown in the below figure:
- After this a new dialouge box appears on the screen as we can see in the below given image:
- So now here in this dialouge edit the storys and their heights and other necesseary data.
- So first of all click on the option story 1 in this dialouge box and rename it as Plinth Level and give it a height of 1.5 as mentioned in the above question itself as shown in the below figure:
- And now go to the Story 2 option click there and type Storey 1 and give it a height of 3.
- Similarly click on the option Story 3 and give it of height 3 and rename it as Story 2.
- And click on the option Story 4 and renamas we can see in the below image:
- Upto now we have set the grids and the number of stories and the basic few changes that will be needed in this modeling.
- Below is the image of how it will look like in the 3-D view and the plan view:
- After this we will be closing the 3-D view window and all the unnecessary viewports in order to focus on the floor plan.
- So after closing the 3-D view we will be going to assing the materials.
- And to assign the material we need to go to the option called DEFINE in the file toolbar as shown in the below image:
- After clicking on the Material Property option there will be another dialouge box opens named as Define Materials.
- From there dialouge box click on the option Add New Material as shown in the below figure:
- After clicking on the Add New Material another diaoluge box opens named as Add New Material Property, in that dialouge box there are few other options. Fill all the necessary details in that options.These options are:
- Region : Select as India.
- Material Type : Select as Concrete.
- Standard : Select as Indian.
- Grade : Select as M30.
- Click OK.
- After clicking OK there is another dialouge box that appears named as Material Property Data as shown in the below figure:
- In this dialouge box fill the necessary data that are required in modelling this building as shown below:
- After this go to the option Design property data and then click on the option Modify/Show Material Property Design Data and then there will be another dialouge box that opens named as Material Property Design Data as shown in the below figure:
- Material Name and Type:
- Material Name : Type M30.
- Material Type : Concrete,Isotropic.
- Grade : M30.
- Design Properties for Concrete Materials:
- Concrete Cube Compressive Strength,fck : 30 MPa.
- Leave the option uncheck on the Lightweight Concrete because it is not a high rise buiding.
- And then click OK.
- Now the concrete material has been added into the list.
- Now we have to add the Rebar for the longitudinal reinforcement.
- So in order to do that first we need to go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 500.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- After this similarly add the rebars for the shear reinforcement, in order to do this process go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 415.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- Now the materials have been added as shown in the below figure:
- Click OK.
- After adding the materials to the plan now we will be adding the beams,column and the slab.
- First of all lets add beam,so In order to do that first do to the Detail option in the file toolbar as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Beam 300X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 300.
- And then click on the option Modify/Show Rebar option.
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option M3 Design Only (Beam).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Cover to Longitudinal Rebar Group Centroid:
- Top Bars : 55 mm.
- Bottom Bars : 55 mm.
- And then Click OK.
- Now click on the option properties Modifier in the Frame Section Property Data window as we can see in the below given image:
- After clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 35%.
- Why do we change MI about 35%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for beams should be 35% as we can see in the below image:
- So here we will change the Moment of Inertia upto 35% as we can see in the below image:
- After this click OK.
- The beams have been added.
- Now we will be adding the columns details.
- In order to add the column details as new element in the frame section, first go to the Define option in the file toolbar at the top of the screen and then go to the Frame section ,as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Column 300X550.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 550.
- Width : 300.
as shown in the below figure:
- And then click on the option Modify/Show Rebar option as shown in the below figure:
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option P-M2-M3 Design (Column).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Reinforcement Configuration:
- Check on the Rectangular option.
Confinement Bars:
- Ties.
Check/Design:
- Check on Reinforcement to be designed.
And all the other necessary data require.
- And now click on the option OK.
- Now go to the option Properties modifier at the right hand side of the page.
- And then after clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 70%.
- Why do we change MI about 70%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for columns should be 70% as we can see in the below image:
- So here we will change the Moment of Inertia upto 70% as we can see in the below image:
- Now click the option OK.
- Now we are done with adding the columns and the beams as we can see in the below image:
- After adding the columns and the beams, now we are going to add the slab of 150mm thickness.
- So in order to add the slab,first we need to go to the Define option and then click the option Slab Sections as we can see at the below given image:
- After clicking on the slab sections option a new dialouge box appears on the screen named as Slab Properties and in this there is an option called Add New Property just click on that option as we can see at the below image:
- After clicking on the option Add New Property a new dialouge box opens called Slab Property Data as shown in the below image:
- Fill out all the necessary data.
General data:
- Property Name : Slab 150 mm.
- Slab Material : M30.
- Modelling Type : Membrane
We will not going to check the option Use Special One-Way Load Distribution because here all the slabs are two way slab because the ratio of their length and the breadth is less than 2 ie,
LB=44=1">LB=44=1LB=44=1 which means all the slabs here are two way slab.
Property Data:
- Type : Slab.
- Thickness : 150 mm.
- After filling all the necessary data we will be clicking on the OK option as we can see at the below given image:
- Uptill now we added beams,columns and the slab successfully.
- After this we will be drawing the columns at the plan.
- So in order to create/draw the columns first we need to go to the plan view.
- Here select all storeys at the right bottom of the screen as we can see at the below given image:
- Now to create the columns in a quick way we need to go to the option Quick Draw Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data.
Properties of Object:
- Property : Select Column 300X550.
- Moment Releases : Select Continous.
- And then place the column accordingly. After using the Quick Draw Column option it will become easier to draw the column. This option automatically tells the exact location or the mid-point where we have to put the column in the plan.
- Similarly place all the columns in the same way. After placing the columns in the plan the plan will look like in the below given image:
- The columns have been successfully placed at their places.
- We can see the column placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- Now that the columns have been created,now we will be creating beams and these columns are joining with these beams.
- So in order to create beams first go to the plan view and select all story at the right bottom of the screen as we can see at the below given image:
- Now to create the beams in a quick way we need to go to the option Quick Draw Beams/Columns which are present at the left side of the screen just click on that option as we can see at the below image:
- After clicking on the option Quick Draw Beams/Columns there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Type of Line : Frame.
- Property : Select Beam 300X400.
- Moment Releases : Select Continous.
- And then place the beams accordingly. After using the Quick Draw Beams/Column option it will become easier to draw the beams.
- Similarly place all the beams in the same way. After placing the beams in the plan the plan will look like in the below given image:
- The beams have been successfully placed at their places.
- We can see the beam placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- After placing the columns and beams in the plan, now we have to place a slab.
- In order to place a slab in the plan first of all go to the plan view of the model and then go to the option Quick Draw Floor/Wall which is present at the left hand side of the screen as shown in the below figure:
- After clicking on the option Quick Draw Floor/Wall there will be new dialouge box that opens called properties of the object.
- In that dialouge box we need to provide the all necessary data as shown in the below figure:
Properties of Object:
- Property : Slab 150mm.
- Local Axis : 0.
- Draw Object Using : Grids.
- And then place the slabs accordingly. After using the Quick Draw Floor/Wall option it will become easier to draw the slab just click in the centre of the grid then the slab will be automatically created.
- Similarly place all the slabs in the same way. After placing the slabs in the plan the plan will look like in the below given image:
- The slabs have been successfully placed at their places.
- We can see the slab placement in the 3d view aslo if i have placed them correctly or not as we can see at the given below image:
- Now that the columns hace been placeed at their respective positions now go to the Assign tab which is present at the top of the screen and from there choose an option called Frame section and then the option Local Axes as we can see in the below image:
- After clicking on the option local axes a new dialoyge box opens named as Frame Assignment- Local Axes as shown in the below image:
- In this dialouge box there is an option called Define Orientation so just click on the option Rotation by Angle and give the 180 degree angle just as shown in the below figure:
- After placing the slab on all the storeys we will be assigning the base of the building as the pinned.
- In order to do that first we need to go to the plan view.
- And for assigning the base of the building we will be working on the base plan.
- And select only one story that is base storey because we have to assign the base.
- Now select all the joining points of the plan as shown in the below figure:
- Now go to the Assign option in the File toolbar then click on the Joint and then click on the Restraints as shown in the below image:
- After clicking on the option Restraints a new dialouge box opens up named as Joint Assignment-Restraints.
- In that dialouge box there are other options in Fast Restraints column just click on the option Pin then select the base as pin as shown in the below image.
- And then click on the option APPLY and then OK.
- Now we will be adding the loads in the plan.
- So in order to add these loads first go to the Define option which is present at the top of the ETABS screen and then click on the option Load Patterns just as shown in the below figure:
- After clicking on the Load Patterns option a new dialouge box opens named as Define Load Patterns just as shown in the below figure:
- Now we have to define the loads in the Loads sections like Loads (Dead load or live load or any other load),the type of load etc just fill this section with the appropriate loadings just as shown in the below figure:
- Now the loads have been assigned accordingly as we can see at the above image.
- Now we have to edit the seismic loads like Eqx,Eqx+,Eqx- etc.
- So in order to do that just click on the option Modify Lateral Load... and then a new dialouge box opens named as Indian IS 1893:2016 Seismic Loading as shown in the below figure:
- First we edit the Eqx load.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx just as shown in the below image:
- Similarly do the same procedure for the Eqx+.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx+ just as shown in the below image:
- For Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqx- just as shown in the below image:
- Now similarly the same procedure for the Eqy as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy just as shown in the below image:
- Now similarly the same procedure for the Eqy+ as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy+ just as shown in the below image:
- Now similarly the same procedure for the Eqy- as of the Eqx-.
- For doing this we need to go to the option Modify Lateral Load... a new dialouge box opens.
- In that dialouge box fill out all the necessary details regarding the load Eqy- just as shown in the below image:
- At last click OK as shown in the below figure:
- Now we will be assigning the live loads to this model.
- In order to assign the live loads first we have to keep the storeys as the Similar Story we can find that option at the bottom of the right hand side of screen as we can see in the below given image:
- After keeping the similar stories we need to select the all shells as we can see in the below given image:
- After selecting the shells go to the option Assign at the top of the screen there will be an option called Assign and from that option there will be another option called Shell Loads from there select option Uniform and then clock just as shown in the below figure:
- After clicking the Uniform option from the Assign tab there will be another dialouge box named as Shell Load Assignment-Uniform as we can see in the below given image:
- Fill the all necessary data in this dialouge box.
Load Pattern:
- Load Pattern Name : Live.
Uniform Load:
- Load : 1.5KN/m2.
- Direction : Gravity.
Options:
- Check on the option Replace Existing Loads.
- And then click on the option Apply and then OK as shown in the below image:
- After assigning the live loads now we will be assigning the loads on the brick wall or infill wall.
- In order to assign the loads on the infill walls.
- First we have to go to the Select tab and then click on the option select and then Object Type which is seen at the upper side of the screen as shown in the below figure:
- After clicking on the Object Type option a new dialouge box opens named as Select by Object Type here select the option Beams.
- After selecting the option beam just click on the option Select and then Close as shown in the below image:
- By doing this all the beams have been selected just by a single click.
- Afte this go to the Assign tab at the top of the screen and there select option Frame Loads and then option Distributed just as shown in the below figure:
- After selecting the option Distributed another dialouge box appears on the screen named as Frame Load Assignment-Distributed just fill out the all necessary information just as shown in the below figure:
- After that just click on the option Apply and then OK.
- Now the 10 KN/m loads have been applied on all the infill walls as shown in the below image:
- After assigning the loads on the infill mass now we will be assigning the mass source.
- In order to do that go to the Define tab and then click on the option Mass Source as shown in the below figure:
- After clicking on the Mass Source option a new dialouge box appears on the screen from there select option Modify/Show Mass Source.
- After selecting the Modify/Show Mass Source another dialouge box appears named as Mass Source Data as shown in the below image:
- Fill out all the necessary data in this section as shown below in the given image:
- And then click OK.
- After assigning the loads on the infill mass now we will be assigning the load combinations.
- So in order to do that go to the Define tab whic is present at the top of the ETABS screen just click on the Define tab and then click on the another option named load combination just as shown in the below image:
- After clicking on the Load Combination a new dialouge box opens named as Load Combinations.
- And then click on the option Add Default Design Combos as shown in the below image:
- After clicking on the option Add Default Design Combos there will be another dialouge box that opens named as Add Default Design Combinations as shown in the below given figure:
- In that dialouge box just click on the option Concrete Frame Design and check on the Convert to User Combinations (Editable) just as shown in the below figure:
- Now the load combinations already have been created by the software itself we can see the loadings in the below given image:
- Now after assigning the load combinations we will be assigning the diaphgram.
- And in order to do that first we have to go to the option Select which is present at the top of the screen then click on the option Select and then go to the option Object Type and then option Floor just as shown in the below image:
- After clicking on the Object Type there will be another dialouge box named as Select by Object Type as shown in the below image:
- Select the object type as Floor and then click on the option Select ad then Close as shown in the below image:
- Now click on the option Assign and then select Shell and then Diaphgrams as shown in the below figure:
- After clicking on the option Diaphgrams there will be another dialouge box named as Shell Assignment- Diaphragms.
- Click on the option D1 and then click on the option Apply and then OK as shown in the below image:
- After clicking on the option Apply The below is the result:
- And now after assigning the diaphragm now we will be doing Model Check.
- So in order to do the Model Check first we go to the file tab there will be an option called Analyse click on that option after that click on the option Check the model just as shown in the below image:
- After this a new dialouge box appears on the screen named as Check Model.
- In that dialouge box just click on all the other options.
- And then just click OK just as shown in the below image:
- After clicking on the OK option the new window named as Warnings opens up to show any warning jus as shown in the below image:
- Now we will be doing run analysis.
- In order to do the Run analysis just press f5 or there is an option in the Analyse tab as shown in the below image:
- This is how the buildin will look like after the analysis shown in the below image:
(E) For Building E(10 Storey building with varying column size along building height):
Given Data for Building E:
- Description: 10 Storey building with varying column size along building height.
- Number of storeys 10.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : Upper 5 storeys the column sizes are 400X400mm.
Below 5 Storey the column sizes are 600X600mm.
- After completing the Model Initialization process another dialouge box appears on the screen named as New Model Quick Template as shown in the below figure:
- First of all we need to create grids according to the plan given in the question. So for creating grids click on the option Custom Grid Spacing. There is another option called Edit Grid Data as shown in the below figure:
- After clicking on the option Edit Grid Data there is another window that opens named as Grid System Data as shown in the below figure:
- Now set the all necessary data in this Grid System Data option. Our X and Y grid sizes are 4 X 4. We have 3 columns and 4 rows that means we have 3 blocks in the Y-direction and 4 blocks in the X-direction.
- Now set the all necessarey data in the given table as shown in the below figure:
- After assigning the grids now we have to assign the number of storys that our building have.
- So in order to do that first we need to go to the option Custom Story Data and then click on the option Edit Story Data as shown in the below figure:
- After this a new dialouge box appears on the screen as we can see in the below given image:
- So now here in this dialouge edit the storys and their heights and other necesseary data.
- So first of all click on the option story 1 in this dialouge box and rename it as Plinth Level and give it a height of 1.5 as mentioned in the above question itself as shown in the below figure:
- And now go to the Story 2 option click there and type Storey 1 and give it a height of 3.
- Similarly click on the option Story 3 and give it of height 3 and rename it as Story 2.
- And click on the option Story 4 and rename it as Story 3 and similary rename the other storeys upto storey 10 we can see in the below image:
- Upto now we have set the grids and the number of stories and the basic few changes that will be needed in this modeling.
- Below is the image of how it will look like in the 3-D view and the plan view:
- After this we will be closing the 3-D view window and all the unnecessary viewports in order to focus on the floor plan.
- So after closing the 3-D view we will be going to assing the materials.
- And to assign the material we need to go to the option called DEFINE in the file toolbar as shown in the below image:
- After clicking on the Material Property option there will be another dialouge box opens named as Define Materials.
- From there dialouge box click on the option Add New Material as shown in the below figure:
- After clicking on the Add New Material another diaoluge box opens named as Add New Material Property, in that dialouge box there are few other options. Fill all the necessary details in that options.These options are:
- Region : Select as India.
- Material Type : Select as Concrete.
- Standard : Select as Indian.
- Grade : Select as M30.
- Click OK.
- After clicking OK there is another dialouge box that appears named as Material Property Data as shown in the below figure:
- In this dialouge box fill the necessary data that are required in modelling this building as shown below:
- After this go to the option Design property data and then click on the option Modify/Show Material Property Design Data and then there will be another dialouge box that opens named as Material Property Design Data as shown in the below figure:
- Material Name and Type:
- Material Name : Type M30.
- Material Type : Concrete,Isotropic.
- Grade : M30.
- Design Properties for Concrete Materials:
- Concrete Cube Compressive Strength,fck : 30 MPa.
- Leave the option uncheck on the Lightweight Concrete because it is not a high rise buiding.
- And then click OK.
- Now the concrete material has been added into the list.
- Now we have to add the Rebar for the longitudinal reinforcement.
- So in order to do that first we need to go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 500.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- After this similarly add the rebars for the shear reinforcement, in order to do this process go to the option Add New Material as shown in the below figure:
- After this a new dialouge box appears on the screen named as the Add New Material Property
- Fill all the necessary details like Region, material type,standard etc:
- Region : Select India.
- Material Type : Select Rebar.
- Stnadard : Indian.
- Grade : HYSD Grade 415.
as shown in the below figure:
- After filling out the all necessary details in this section and then click OK.
- Then there is another window that opens named as the Material Property Data in that window fill out the necessary information as shown in the below figure:
- Click OK.
- Now the materials have been added as shown in the below figure:
- Click OK.
- After adding the materials to the plan now we will be adding the beams,column and the slab.
- So in order to add columns first we need to change the view setting of the model first.
- So in order to do so first go to the option view option settings, we can find this option easily at the front tool ribbons of the Etab.
- So go to the view option settings and uncheck the other structural members because we have to assign different columns for the different storeys.
- So currently we don't need to view the beams and slab currently.
- Now go to the option View and then go to the option Set display option just as shown in the below image:
- After that a new dialouge box opens named as Set view option just as shown in the below figure:
- Now uncheck the option beams and floors in that dialouge box because during this process we don't need this just as shown in the below image:
- Now we will be assigning the building limits,select the columns and assign them the required column sizes.
- Since we need the different column size upto storey 5 that is 5 top floor and different column size for the 5 below floor.
- So first we need to edit the top 5 floor first and after that below 5 storey.
- So we need to set the building limits and to do this first we need to go to the option view and then option set building view limits just as shown below in the image:
- After clicking the Set Building view limits another dialouge box opens named as Set Building View Limits just as shown in the below figure:
- Then apply the all necessary data in the dialouge box:
Set Story Range:
- Top Story : Story 10.
- Bottom Story : Story 6.
Just as shown in the below figure:
- This will be shown in 3D as shown in the below image:
- Now we will be adding the columns in the first 5 storey building.
- In order to add the column details as new element in the frame section, first go to the Define option in the file toolbar at the top of the screen and then go to the Frame section ,as shown in the below figure:
- After clicking on the option Frame Section The new dialouge box appears on the screen, in that dialouge box there will be an option called Add New Property just click on that option as shown in the below figure:
- After clicking on the option Add New property another dialouge box appears on the screen named as Frame Property Shape Type.
- From that dialouge box choose the desired shape,here i am choosing the Concrete rectangular as shown in the below image:
- Click OK.
- After clicking the OK there will be another dialouge box name as Frame Section Property Data as shown in the below figure:
- In that dialouge box fill out the all necessary data which is required to model this building as shown in the above figure.
General data:
- Property Name : Type Column 400X400.
- Material : M30.
Shape:
- Section Shape : Concrete Rectangular.
Select Dimensions:
- Depth : 400.
- Width : 400.
as shown in the below figure:
- And then click on the option Modify/Show Rebar option as shown in the below figure:
- Another window appears on the screen named as Frame Section Property Reinforcement Data as shown in the below image:
- Fill out the necessary details in that dialouge box.
Design Type:
- Check on the option P-M2-M3 Design (Column).
Rebar Material:
- Longitudinal Bars : Select HYSD500.
- Confinements Bars (Ties) : HYSD415.
Reinforcement Configuration:
- Check on the Rectangular option.
Confinement Bars:
- Ties.
Check/Design:
- Check on Reinforcement to be designed.
And all the other necessary data require.
- And now click on the option OK.
- Now go to the option Properties modifier at the right hand side of the page.
- And then after clicking on the Modify/Show Modifiers option a new window/dialouge box opens. In that box we need to change the Moment of Inertia about axis upto 70%.
- Why do we change MI about 70%? Because of the Clause No. 6.4.3.1 in IS 1893 (Part 1):2016. Because this clause states that the Moment of Inertia about axis for columns should be 70% as we can see in the below image:
- So here we will change the Moment of Inertia upto 70% as we can see in the below image:
- Now click the option OK.
- Now we will be editing the bottom storeys from the previous stories of the building, The other bottom column are of size 600X600 mm just as shown in the below image:
- Now assign the columns upto the top 5 stories just as shown in the below figure:
- Now we have assigned the columns size upto the 5 Stories as we can see in the above image. Now we will be assigning the other column size of the remaining stories.
- So in oder to do that first we need to go to the option Assign tab and then section property just as shown in the below image:
- After clicking on that option a new dialouge box opens named as Frame Assignment- Section Property choose the column of size 400X 400 as we can see in the below image:
- Now the column of size 400X400 has been assigned to the top stories as we can see in the below image:
- Now we will be assigning the other stories with different column sizes of 600X600 mm.
- For this just go to the option View and go to the another option called Set building view limits as we can see in the below image:
- After this a new dialouge box opens named as Set building view limits as we can see in the below image:
- Select the top story as Story 10 and the Bottom story as Story 6 and the click on the option Show All and then click Ok just as shown in the below image:
- Now the columns of different sizes have been assigned to the stories as we can see the different sizes of column in the below given 3D image:
- Now after assigning the columns of different sizes to the different stories we haved to make visible the floors and the beams and then click the option Apply and then OK as shown in the below image:
- Now everything is visible in the plan as we can see in the below image:
- After this now we will be selecting the slab and assign the diaphragram.
- In order to do so first go to the option Select toolbar then select option Properties and then select Slab section just as shown in the below image:
- After this a new .dialouge box opens named as Select by slab property in that dialouge box select the Slab option and then click Select and then click on the Close option just as shown in the below image:
- After this assign the diaphragms to do this go to the Assign option and then the other option Shell and then click on the option Diaphragms just as shown in the below image:
- After this a new dialouge box opens named as Shell assignment- Diaphragms from here choose the option D1 and then click Apply and then OK just as shown in the below image:
- The diaphragms have been assigned just as shown in the below given image:
- Now we will be doing the run analysis.
- To do the Run analysis just press F5 or click the shortcut which is present at the front ribbon pannel or just go to the option Analyze and there will be another option called Run Analysis just click on that just as shown in the below image:
- After Run analysis the deflected shape is now visible just as shown in the below image:
(F) For Building F(10 Storey building):
Given Data for Building F:
- Description: 10 Storey building.
- Number of storeys 10.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 600X600 mm.
- So this building F is a 10 stories building with same column sizes of 600X600 mm.
- So in order to do this question first we need to save as the Building E project file as Building F. After saving the file we will be able to do the editing in the project.
- As this is a 10 stories building with the same column sizes so there is nothing much to change.
- So after saving the file as Building F first we begin with hiding the beams and the floors again in order to do the project.
- So lets hide the beams and the floors and in order to do so first we need to go to the option View and then go to the option Set display option just as shown in the below image:
- After that a new dialouge box opens named as Set view option just as shown in the below figure:
- Now uncheck the option beams and floors in that dialouge box because during this process we don't need this just as shown in the below image:
- For this just go to the option View and go to the another option called Set building view limits as we can see in the below image:
- After this a new dialouge box opens named as Set building view limits as we can see in the below image:
- Select the top story as Story 10 and the Bottom story as Story 6 and the click on the option Show All and then click Ok just as shown in the below image:
- Now select all the columns just as shown in the below image:
- Now we have assigned the columns size upto the 5 Stories as we can see in the above image. Now we will be assigning the other column size of the remaining stories.
- So in oder to do that first we need to go to the option Assign tab and then section property just as shown in the below image:
- After clicking on that option a new dialouge box opens named as Frame Assignment- Section Property choose the column of size 600X 600 as we can see in the below image:
- Now the column of size 600X600 has been assigned to the top stories as we can see in the below image:
- Now we will be assigning the other stories with same column sizes of 600X600 mm.
- For this just go to the option View and go to the another option called Set building view limits as we can see in the below image:
- After this a new dialouge box opens named as Set building view limits as we can see in the below image:
- Select the top story as Story 10 and the Bottom story as Story 6 and the click on the option Show All and then click Ok just as shown in the below image:
- Now the columns of different sizes have been assigned to the stories as we can see the different sizes of column in the below given 3D image:
- Now after assigning the columns to the different stories we haved to make visible the floors and the beams and then click the option Apply and then OK as shown in the below image:
- Now everything is visible in the plan as we can see in the below image:
- After this now we will be selecting the slab and assign the diaphragram.
- In order to do so first go to the option Select toolbar then select option Properties and then select Slab section just as shown in the below image:
- After this a new .dialouge box opens named as Select by slab property in that dialouge box select the Slab option and then click Select and then click on the Close option just as shown in the below image:
- After this assign the diaphragms to do this go to the Assign option and then the other option Shell and then click on the option Diaphragms just as shown in the below image:
- After this a new dialouge box opens named as Shell assignment- Diaphragms from here choose the option D1 and then click Apply and then OK just as shown in the below image:
- The diaphragms have been assigned just as shown in the below given image:
- Now we will be doing the run analysis.
- To do the Run analysis just press F5 or click the shortcut which is present at the front ribbon pannel or just go to the option Analyze and there will be another option called Run Analysis just click on that just as shown in the below image:
- After Run analysis the deflected shape is now visible just as shown in the below image:
(G) For Building G(25 Storey building with varying column size along building height):
Given Data for Building G:
- Description: 25 Storey building with varying column size along the building height.
- Number of storeys 25.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : Upper 5 stories : 400X400 mm.
Middle 10 storeis : 600X600 mm.
Bottom 10 Stories : 800X800 mm.
- So this building G is a 25 stories building with different column sizes along the building's height.
- So in order to do this question first we need to save as the Building F project file as Building G. After saving the file we will be able to do the editing in the project.
- As this is a 25 stories building with the different column sizes.
- So after saving the file as Building G first we begin with hiding the beams and the floors again in order to do the project.
- So in order to begin the project first of all we have to edit the stories.
- In order to edit the stories first we need to go to the Edit toolbar which is present at the top of the screen and then just click on the option Edit story and Grid systems just as shown in the below given image:
- After clicking that option a new dialouge box opens named as Edit story and Grid System Data in that dialouge box there is another option named Modify/Show story data just click on that option just as shown below in the given image:
- After clicking on that option another dialouge box opens named as Story data in that dialouge box edit the number of stories according to the requirement just as shown in the below given image:
- So from here we will be editing our stories data,here we need more 15 stories because this is a 25 story building just as shown in the below image:
- So after this we have to define the three different column sizes.
- So in order to do that first we need to go to the Define toolbar just click on that and adter that click on the option Section Properties and then Frame secttion just as shown in the below image:
- After this a new dialouge box opens named as Frame Properties in that dialouge box we can see that we already have two column sizes that is column 400X400 and column 600X600 mm.
- But we have to add one another column of different size of 800X800 mm. So just go to the option Modify/Show Property just modify the 600X600 mm column into Column 800X800 mm and create another property for Column 600X600 mm just as shown in the below image:
- All the three different columns with different sizes have been created as we can see in the below image:
- So lets hide the beams and the floors and in order to do so first we need to go to the option View and then go to the option Set display option just as shown in the below image:
- For this just go to the option View and go to the another option called Set building view limits as we can see in the below image:
- After this a new dialouge box opens named as Set building view limits as we can see in the below image:
- Select the top story as Story 25 and the Bottom story as Story 21 and the click on the option Show All and then click Ok just as shown in the below image:
- Now select all the columns just as shown in the below image:
- Now we have assigned the columns size upto the 5 Stories as we can see in the above image. Now we will be assigning the other column size of the remaining stories.
- So in oder to do that first we need to go to the option Assign tab and then section property just as shown in the below image:
- After clicking on that option a new dialouge box opens named as Frame Assignment- Section Property choose the column of size 400X 400 as we can see in the below image:
- Now the column of size 400X400 has been assigned to the top stories as we can see in the below image:
- Now we will be assigning the other stories with different column sizes.
- For this just go to the option View and go to the another option called Set building view limits as we can see in the below image:
- After this a new dialouge box opens named as Set building view limits as we can see in the below image:
- Select the top story as Story 11 and the Bottom story as Story 20 and the click on the option Show All and then click Ok just as shown in the below image:
- Now the columns of different sizes have been assigned to the stories as we can see the different sizes of column in the below given 3D image:
- After this once again go to the option View and go to the another option called Set building view limits as we can see in the below image:
- After this a new dialouge box opens named as Set building view limits as we can see in the below image:
- Select the top story as Story 25 and the Bottom story as Story Base and the click on the option Show All and then click Ok just as shown in the below image:
- And below is the result in 3D:
- Now after assigning the columns to the different stories we haved to make visible the floors and the beams and then click the option Apply and then OK as shown in the below image:
- Now everything is visible in the plan as we can see in the below image:
- After this now we will be selecting the slab and assign the diaphragram.
- In order to do so first go to the option Select toolbar then select option Properties and then select Slab section just as shown in the below image:
- After this a new .dialouge box opens named as Select by slab property in that dialouge box select the Slab option and then click Select and then click on the Close option just as shown in the below image:
- After this assign the diaphragms to do this go to the Assign option and then the other option Shell and then click on the option Diaphragms just as shown in the below image:
- After this a new dialouge box opens named as Shell assignment- Diaphragms from here choose the option D1 and then click Apply and then OK just as shown in the below image:
- The diaphragms have been assigned just as shown in the below given image:
- Now we will be doing the run analysis.
- To do the Run analysis just press F5 or click the shortcut which is present at the front ribbon pannel or just go to the option Analyze and there will be another option called Run Analysis just click on that just as shown in the below image:
- After Run analysis the deflected shape is now visible just as shown in the below image:
(H) For Building H(25 Storey building):
Given Data for Building H:
- Description: 25 Storey building.
- Number of storeys 25.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 800X800 mm.
- So this building H is a 25 stories building.
- So in order to do this question first we need to save as the Building G project file as Building H. After saving the file we will be able to do the editing in the project.
- As this is a 25 stories building with the same column sizes.
- So after saving the file as Building H first we begin with hiding the beams and the floors again in order to do the project.
- Here we do not need to change the stories of the building as the previous building was also a 25 story building.
- So first of all hide the beams and the floors and in order to do so first we need to go to the option View and then go to the option Set display option just as shown in the below image:
- After this select all the columns just as shown in the below image:
- Now we have to assigned the columns size of 800X800 mm as we can see in the above image. Now we will be assigning the other column size of 800X800 mm.
- So in oder to do that first we need to go to the option Assign tab and then section property just as shown in the below image:
- After clicking on that option a new dialouge box opens named as Frame Assignment- Section Property choose the column of size 800X 800 as we can see in the below image:
- Now the column of size 800X800 has been assigned to the top stories as we can see in the below image:
- Now after assigning the columns to the different stories we haved to make visible the floors and the beams and then click the option Apply and then OK as shown in the below image:
- Now everything is visible in the plan as we can see in the below image:
- After this now we will be selecting the slab and assign the diaphragram.
- In order to do so first go to the option Select toolbar then select option Properties and then select Slab section just as shown in the below image:
- After this a new .dialouge box opens named as Select by slab property in that dialouge box select the Slab option and then click Select and then click on the Close option just as shown in the below image:
- After this assign the diaphragms to do this go to the Assign option and then the other option Shell and then click on the option Diaphragms just as shown in the below image:
- After this a new dialouge box opens named as Shell assignment- Diaphragms from here choose the option D1 and then click Apply and then OK just as shown in the below image:
- The diaphragms have been assigned just as shown in the below given image:
- Now we will be doing the run analysis.
- To do the Run analysis just press F5 or click the shortcut which is present at the front ribbon pannel or just go to the option Analyze and there will be another option called Run Analysis just click on that just as shown in the below image:
- After Run analysis the deflected shape is now visible just as shown in the below image:
(J) For Building J(25 Storey building with imposed mass 10% larger than building H):
Given Data for Building J:
- Description: 25 Storey building with imposed mass 10% larger than building H.
- Number of storeys 25.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 800X800 mm.
- So this building J is a 25 stories building with imposed mass of 10% larger than building H.
- So in order to do this question first we need to save as the Building H project file as Building J. After saving the file we will be able to do the editing in the project.
- As this is a 25 stories building with the same column sizes.
- Here we do not need to change the stories of the building as the previous building was also a 25 story building. In this model J there are structural changes imposed as we need to increase the mass upto 10%.
- So in order to do that first we need to go to the option Select present at the top of the screen and then select the option Properties and then Slab Section just as shown in the below figure:
- After this a new dialouge box opens named as Select by slab property and select the slab click Select and then click Close just as shown in the below given image:
- Now the slabs of all the floors have been selected just as shown in the below image:
- After selecting the slabs of all the floors now we have to increase the mass by 10%. So in order to do that first go to the option Assign and then Shell loads and then go to the option Uniform just as shown in the below given image:
- After this a new dialouge box opens named as Shell Load Assignment-Uniform.
- In that dialouge box increase the load by 10% i.e, 3.3 Kn/m2 and then click Apply and then OK just as shown in the below imge:
- Now we will be doing the run analysis.
- To do the Run analysis just press F5 or click the shortcut which is present at the front ribbon pannel or just go to the option Analyze and there will be another option called Run Analysis just click on that just as shown in the below image:
- After Run analysis the deflected shape is now visible just as shown in the below image:
(K) For Building K(25 Storey building with imposed mass 20% larger than building H):
Given Data for Building K:
- Description: 25 Storey building with imposed mass 20% larger than building H.
- Number of storeys 25.
- Number of bays:
- In X-direction : 4
- In Y-direction : 3
- Column Dimensions : 800X800 mm.
- So this building K is a 25 stories building with imposed mass of 20% larger than building H.
- So in order to do this question first we need to save as the Building J project file as Building K. After saving the file we will be able to do the editing in the project.
- As this is a 25 stories building with the same column sizes.
- Here we do not need to change the stories of the building as the previous building was also a 25 story building. In this model K there are structural changes imposed as we need to increase the mass upto 20%.
- So in order to do that first we need to go to the option Select present at the top of the screen and then select the option Properties and then Slab Section just as shown in the below figure:
- After this a new dialouge box opens named as Select by slab property and select the slab click Select and then click Close just as shown in the below given image:
- Now the slabs of all the floors have been selected just as shown in the below image:
- After selecting the slabs of all the floors now we have to increase the mass by 10%. So in order to do that first go to the option Assign and then Shell loads and then go to the option Uniform just as shown in the below given image:
- After this a new dialouge box opens named as Shell Load Assignment-Uniform.
- In that dialouge box increase the load by 20% i.e, 3.6 Kn/m2 and then click Apply and then OK just as shown in the below imge:
- Now we will be doing the run analysis.
- To do the Run analysis just press F5 or click the shortcut which is present at the front ribbon pannel or just go to the option Analyze and there will be another option called Run Analysis just click on that just as shown in the below image:
- After Run analysis the deflected shape is now visible just as shown in the below image:
RESULT:
(i) COMPARISON:
(a) Effect of Stiffness on Time Period Between Building E and Building F:
Building E ( It is a 10 storey building with varying column sizes):
Modal Frequency and analysis: 2.74 s
Building F ( it is a 10 strey building with same column sizes):
Modal Frequency and analysis: 2.79 s.
(b) Effect of Stiffness on Time Period Between Building G and Building H:
Building G (25 storey building with varying column sizes):
Modal Periods and Frequencies: 6.66 s.
Building H ( 25 storey building with same size of the columns):
Modal Periods and Frequencies: 7.07 s.
- If we compare the above buildings with the varying sizes of the columns and the different sizes of the columns of 10 storey buildings we can see that there are ot much difference between their modal periods and frequencies.
- But if we see the Building G and Building H with varying column sizes and with the same column sizes of 25 storey buildings we can see that the Building G with varying column size is more stable than the Building H with same column size.
- Because with the same column sizes the mass is lumped at the top stories. And the mass is directly proportional to the lateral load acting on the building that induces more lateral displacement of the building leading to greater time period.
(ii) COMPARISON:
(a) Effect of Mass on Time Period Between Building H, Building K and Building J:
Building H ( 25 storey building with same size of the columns with 3Kn/sq.m imposed load):
Modal Periods and Frequencies: 7.07 s.
Building J (25 storey building with 3.3 Kn/sq.m imposed load):
Modal Periods and Frequencies: 7.09 s.
Building K ( 25 storey building with 3.6 Kn/sq.m imposed load):
Modal Periods and Frequencies: 7.10 s.
- As we can see after observing their Modal Periods and Frequencies of these three buildings we observe that there is not much difference between the time periods of these buildings.
- Sice we have uniform loadings so there is a difference but not that much difference.
(iii) COMPARISON:
(a) Effect of Building Height on Time Period Between Building A, Building B, Building F and Building H:
Building A ( It is a 2 storey building):
Modal Periods and Frequencies: 0.68 s.
Building B ( It is a 5 storey building):
Modal Periods and Frequencies: 0.78 s.
Building F ( It is a 10 storey building):
Modal Periods and Frequencies: 2.79 s
Building H ( It is ia 25 storey building):
Modal Periods and Frequencies: 7.07 s.
- After observing the modal periods and frequencies of the give buildings we can say that the time period increases with the increase in the height of the building.
- It is obvious that if the height of the building increases then the time periods of the building also increase. We can say that the height of the building is directly proportional to the time period according to the IS code so as the height increases time period of the building also increase.
(iv) COMPARISON:
(a) Effect of Column Orientation on Time Period Between Building B, Building C and Building D:
Building B ( It is a 5 storey building of column sizes 400X400 mm):
Modal Periods and Frequencies: 0.78 s.
Building C ( It is a 5 storey building of column sizes 550X300 mm which is oriented in the X-direction):
Modal Periods and Frequencies: 0.87 s.
Building D ( It is a 5 storey building of column sizes 300X550 mm which is oriented in the Y-direction):
Modal Periods and Frequencies: 2.74 s.
- For building B we have same column size of 400X400 mm throughout the building,so the response of the building in each direction should be similar. Because of the same column sizes in both the direction i.e, in X-direction and Y-direction also.
- For building C we have higher column sizes in the X-direction i.e, 550X300 mm and as for the building D we are provided higher column sizes in the Y-direction i.e, 300X550 mm, so it means the deflection of the floor will be higher in building D than the building C.
(v) COMPARISON:
(a) Effect of Flexural Stiffness of Structural Elements on Mode Shapes of Building B:
The flexural Stiffness of Structural Elements on Mode shapes:
- Flexural stiffness of the beams close to the nil (zero inertia) : 2.74 s.
- Full flexural stiffness of the beam : 0.78 s.
- From the above observation we observe that If we don't consider the stiffness property of the beam then we will be getting more than double of the actual time.
(vi) COMPARISON:
(a) Effect of Axial Stiffness of Vertical Members on Mode Shapes of Building H:
- Axial cross-section for columns is close to NIL:
Modal Periods and Frequencies: 8.14 s.
- Full Axial cross-section for columns:
Modal Periods and Frequencies: 7.07 s.
- After observing from the above we can say that the axial stiffness plays an important role in the time period.
(vii) COMPARISON:
(a) Effect of Degree of fixity at Column based on Mode Shapes of Building B:
- Column supports are pinned:
Modal Periods and Frequencies: 0.78 s.
- Column supports are fixed:
Modal Periods and Frequencies: 0.75 s.
- From the above observation we can conclude that the more the fixity of the column lesser the time period and lesser it will get deflected.
- So the time period will have been reduced if the condition is changed from pinned to fixed.