Challenge

Structural Modelling using Etabs 2018

MMeganathan S11 Jul 2022

AIM & INTRODUCTION :

AIM :

To design and analyse the G+7 residential building in zone 5 with the provided informations and the structural model must comply wiht provisions of IS 1893 and IS 13930.

INTRODUCTION :

In E-TABS the stuctural members such as beams, columns and slabs can be created and analysed its bending moment and shear force.

We can Run the Concrete Frame Design fo the created structure to provide required both Longitudinal and shear reinforcement bars automatically.

The values for the created structures can be automatically calculated by E-TABS.

Here in E-TABS we can know the number of Reinforcement bars should be provided for the concrete structures.

From Frame design analysis we can see both Top and Bottom reinforcement figures for each beam sections.

We can display concrete frame design result for Longitudinal and Shear reinforcement.

And also for the Shear wall design such as Pier Longitudinal reinforcement, Pier Shear Reinforcemnt and Edge/Boundary Zone width.

Moreover we can view the concrete beam design information as per IS 456:2000.

The Design details of the overall structures can also be viewed as Summary, Flexural Details, Shear Details, Envelope.

The Earthquake forces in both X and Y direction can be added and the deformations can be analysed.

Likewise the Respond spectrum in X and Y directions can also be analysed.

The shear wall stiffness and the base shear stiffness can be seen in the table after analysing.

PROCEDURE :

First open the ETABS software and click File < New Model to open a new workspace to create a new Building model.

Then the Model information Tab will be opened, there click Use Built-in Settings with.

Followed by change Display Units = Metric SI, Region for Default Materials = India, Steel section Database = Indian, Steel Design Code = IS 800 2007, Concrete Design code = IS 456 2000 and click OK.

After that the New model template Tab will be opened, there click Custom grid spacing < Edit grid data.

Then the Grid system Data Tab will be opened, there in X Grid Data Add Grid ID = A,B,C,D with appropriate X-ordinates.

Likewise in Y Grid Data Add Grid ID = 1,2,3,4,5,6 with appropriate Y-ordinates and click OK.

After that the Story Data Tab will be opened, here to add extra required stories above the default stories.

For that Right click over the last story and select Add story < Keep existing story heights.

Now in Add story Tab add the Story height = 3 and the Number of Added stories = 7 and click OK.

Here we can see the extra stories are added above the previous story and we can give appropriate name to them such as from Base to Mumty.

Then the Story 1 should be set as Master story and the remaining stories upto Story 9 should be set as Similar to story 1.

Atlast the grids for all the stories can be created from Base to the Mumty level.

Then we have to define the material properties for Columns, Beams, Slabs and Shear walls.

For that click Define < Material Properties then the Define Materials Tab will be opened.

In opened tab Click Add New material and select Region = India, Material Type = Concrete, Standard = Indian, Grade = 30 and click OK.

Then Material Property Data Tab will open, here change the Material Name = M30, Material Type = Concrete and click OK.

Likewise the Material property for Shear Rebar has to be defined.

For that the same procedure should be followed such as click Define < Material Properties then the Define Materials Tab will be opened.

In opened tab Click Add New material and select Region = India, Material Type = Rebar, Standard = Indian, Grade = HYSD Grade 415 and click OK.

Then Material Property Data Tab will open, here change the Material Name = HYSD415, Material Type = Rebar and click OK.

Material property for Longitudinal Rebar also be defined.

For that the same procedure should be followed such as click Define < Material Properties then the Define Materials Tab will be opened.

In opened tab Click Add New material and select Region = India, Material Type = Rebar, Standard = Indian, Grade = HYSD Grade 550 and click OK.

Then Material Property Data Tab will open, here change the Material Name = HYSD550, Material Type = Rebar and click OK.

Followed by the Frame sections for beams, columns has to be defined.

For that click and select Define < Section properties < Frame sections.

Then the Frame Properties Tab will open, here click Add New Property.

After clicking, Frame Property shape type Tab will open.

From there select Rectangular Section under the concrete and click OK.

Then the Frame Section Property Data Tab will open, First we should create a Beam Frame section Property.

Here Change the Property Name = B400x500, Material = M30, Depth = 500mm, Width = 400mm.

To make the created Frame Section as Beam section Click Modify/Show Modifiers.

Then the Frame section Property Reinforcement Data Tab will open, here we should change the Design Type.

For that Select M2 Design Only (Beam) > Design Type, Longitudinal Bars = HYSD550, Confinement Bars (Ties) = HYSD550 and click OK.

Likewise for Columns Sections from Frame Properties Tab click Add New Property.

After clicking, Frame Property shape type Tab will open.

From there select Rectangular Section under the concrete and click OK.

Then the Frame Section Property Data Tab will open, First we should create a Column Frame section Property.

Here Change the Property Name = C450x600, Material = M30, Depth = 600mm, Width = 450mm.

To make the created Frame Section as Column section Click Modify/Show Modifiers.

Then the Frame section Property Reinforcement Data Tab will open, here we should change the Design Type.

For that Select P-M2-M3 Design (Column) > Design Type, Longitudinal Bars = HYSD550, Confinement Bars (Ties) = HYSD550 and click OK.

Likewise the Slab sections for Slab has to be defined.

For that click and select Define < Section properties < Slab sections.

Then Slab Properties Tab will open, here click Add New Property.

After clicking, Slab property Data Tab will open here change the General Data appropriately.

And make Property Name = S150, Slab Material = M30, Thickness = 150mm and click OK.

Atlast the Wall sections for Shear wall has to be defined.

For that click and select Define < Section properties < Wall sections.

Then Wall Properties Tab will open, here click Add New Property.

After clicking, Wall property Data Tab will open here change the General Data appropriately.

And make Property Name = Shear Wall, Wall Material = M30, Modelling Type = Shell-Thin, Thickness = 300mm and click OK.

NOTE : Before clicking OK, we should make sure whether the Check box (Include Automatic Rigid Zone Area Over Wall) is selected.

Now we can start Draw the created Sections all over the Grids.

To create Beams, Select the Tool named Quick Draw Beams/Columns (Plan,Elev,3D) at the left corner of the workspace Toolbar menu.

And select the created Beam Size B400x500 in the Properties of Object Tab < Property = B400x500.

Before assigning the Beams all over the grids of the Plan, we should make sure the beams should be provided to all stories.

For that first click and select Set Plan View and the Select Plan View Tab will open.

In the opened Tab, Select Story 1 and click Ok.

Then we have to be make sure whether All Stories option is enables to assign the beams to all stories.

Then we should click over the grid lines to assign the Beams.

After assigning the Beams all around the created model grids, the Columns should be assigned at the intersections of the assigned Beams.

For that Select the Tool named Quick Draw Columns (Plan,3D) at the left corner of the workspace Toolbar menu.

And select the created Column Size C450x600 in the Properties of Object Tab < Property = C450x600.

Then we should click and assign the Columns at the intersections of all beams.

After assigning all columns, we can see all the Column Orientations are in X direction.

But some of the columns are needs to be in Y direction as appropriate.

For that click and select the columns that needs to changed in its into Orientation.

Then click and select Assign < Frame < Local Axes to open Frame Assignment - Local Axes Tab.

From the opened Tab, make Rotate by angle = 90 degree > General Orientation > Define Orientation and click OK.

Here we can see that the selected columns are rotated 90 degree from its Orientation from X to Y direction.

Followed by beams and columns, the Slabs at the floor level should be assigned.

For that click and select Set Plan view then we can see Select Plan View Tab will be opened.

In the opened Tab select Story 1 and click Apply to view the Story 1 view plan.

Then we have to make sure whether Similar Stories option is enabled to assign the beams to all the simillar stories of story 1.

By making the stories to Similar, we can ignore Slabs apply at the Base level.

Then the Slabs should be assigned inbetween the assigned Beams and columns.

For that Select the Tool named Quick Draw Floors (Plan,3D) at the left corner of the workspace Toolbar menu.

And select the created Slab Thickness = 150mm in the Properties of Object Tab < Property = S150.

Below we can see the building model with assigned Beams, Columns and Slabs.

Then again click Set plan View and from Select Plan view Tab select Mumty level and click Apply to open Mumty level Plan view.

Here we have to make sure whether One Stories option is enabled to edit Slabs at Mumty level.

By making the editable stories to One Stories at Mumty level, we can ignore Slabs edited other than Mumty level.

Here Delete all the other Slabs assigned at Mumty level and leave the slab above the area for Steps from Story1 to Mumty.

Now, we should assign the Shear Walls at the approprite location of the building model.

To assign shear walls upto the Roof level, Click Set plan view to open Select plan view tab and select Roof Level and click Apply.

Then we have to Delete a part of beams at the place where we want to assign Shear walls.

For that we should Replicate the beams upto the size of the Shear wall to break the intersection points of the replicated beams.

So click and select beam which has to replicated at X or Y direction, then select Edit < Replicate.

After selecting the Replicate Tab will open, type the recommended distance where the beam should be replicated and click Apply.

Here we have typed dy = -1.2 from Linear < Increment Data < dy = 0m, dy = -1.2m .

After replicating all the required beams, select all the replicated beams and other intersecting beams.

Then click and select Edit < Edit Frames < Divide Frames to open Divide selected Frames Tab.

In opened Tab select Break at intersections with selected frames and joints.

And click Apply to break the intersection points of all the Beams replicated and selected.

Then we can Delete the beams at the break points to assign the Shear walls.

Now click and select Draw Wall (plan) tool at the left corner of the workspace toolbar menu.

Then select the created Shear wall from the Properties of Object tab < Property = Shear wall.

After selecting the appropriate Shear wall property, try assigning the Shear walls at the allocated location.

Below we can see the Shear walls assigned at the appropriate locations symmetrically.

Now we should assign the created Shear walls around the Staircase area mumty level.

For that Set the Plan view to mumty level and make the stories to One story.

After that select the deleted beam area to assign the shear wall at the Mumty level.

Then we should make Restraints of the Base Level as Fixed from the pinned (default) .

For that first set the Plan view to Base level from Set Plan view < Select Plan View < Base and click Apply.

After setting the Plan view to Base, click and select Assign < Joint < Restraints .

Then the Joint Assignment - Restraints Tab will open, here the Fixed joint has to be selected.

For that select First icon below the Fast Restraints and click Apply.

After assigning the Fixed Restraints at the base, we should Define the Load Patterns.

For that click and select Define < Load patterns to open Define Load Pattern Tab.

From opened Tab, Add new loads as Dead (Default) = Dead, Live = Live, Brickwall = Super Dead, Finishes = Super Dead and click OK.

Now the Brick Wall Loads (Super Dead) should be applied over the Frames as Distributed Load.

For that first set the Plan view at the Story 1 by selecting Set Plan View < Select plan View < Story1 and click Apply.

Then we have to make sure whether Similar Stories option is enabled to assign the Distributed Loads to all the simillar stories of story 1.

By making the stories to Similar, we can ignore the Load applying to the frames not supporting wall loads such as Roof and Mumty level.

Now Select all the Beam Frames except the shear walls of the plan to assign the Loads over the Beams.

To apply the load, Select Assign < Frame Loads < Distributed to open the Frame Load Assignment - Distributed Tab.

From the opened Tab, Select Load Pattern Name = Brick Wall, and Uniform Load = 5 (Default) and click OK.

After assigning the Distributed load over the Beam frames, we can see the applied load from one story separately.

To view it, click and select the tool named Perspective Toggle at the Top of the workspace Toolbar menu.

Then the Live Load as Uniform load should be applied over the Slabs of all similar stories with slabs assigned.

For that select all the Slabs, then Click and Select Assign < Shell Loads < Uniform to open Shell Load Assignment - Uniform Tab.

From opened Tab, make Load Pattern Name = Live, Load = `2.5 kN/m^2` and click Apply.

After assigning the Uniform load over the Slabs, we can see the applied load from one story separately.

To view it, click and select the tool named Perspective Toggle at the Top of the workspace Toolbar menu.

Likewise the Floor Finishes load as Uniform load should be applied over the Slabs of all similar stories with slabs assigned.

For that select all the Slabs, then Click and Select Assign < Shell Loads < Uniform to open Shell Load Assignment - Uniform Tab.

From opened Tab, make Load Pattern Name = Finishes, Load = `1.5 kN/m^2` and click Apply.

Atlast the Over Head Tank Load of 20 kN (`1kN/m^2`) should be applied separately at Mumty level.

For that Set the Plan view at the Mumty level by clicking Set Plan view < Select Plan View < Mumty and click Apply.

Then select Assign < Shell Loads < Uniform to open the Shell Load Assignment - Uniform Tab.

From opened Tab, make Load Pattern Name = Live, Load = `1 kN/m^2` and click Apply.

Then the Live Load Reduction Factors should be Added for every Stories by reducing gradually from Story1 to Story9.

For that click and select Design < Live Load Reduction Factors to open Live Load Reduction Factor Tab.

From the opened Tab, select User Defined (By stories supported) and click Define.

After click Define, Live Load Reduction By Stories Supported Tab will open.

Here, we should add the add the all story names along with the Load Reduction value.

It should be reducing gradually from 1 to 0.6 and not less than 0.6 and click OK.

Then we should calculate the Ta (Approximate Natural Time period) value of the building in both X and Y direction.

To get that refer IS-Part I-1893 2016, Clause 7.6.2 c) All other buildings `Ta = 0.09h/sqrtd`

Where,

h = Height of building.

d= Base dimension of the building at the plinth level along the considered direction of earthquake shaking, in m.

To know the Base dimension (d) of the building select the Beam Drawing tool and try to measure the Base Dimension (d) value.

Below the image we can see the Base Dimension (d) = 19.8m .

Then to know the Height of the building (h), we should visit the Elevation height from the Story data Tab.

For that click and select Edit < Edit Stories and Grid System to open Edit Stories and Grid System Data Tab.

After opening of the Tab, click the Modify/Show Story Data option to open the Story Data Tab.

In the opened Story Data Tab, we can see the height of the building as Elevation m = 33m.

Then we should find out the Time period the Earthquake in X direction by using the formula obtained from IS 1893-Part I-2016.

`Ta = 0.09h/sqrtd`

`Ta = 0.09 (33)/sqrt(19.8)`

Ta= 0.66

Before that we should create Load Patterns for all Loads along with Seismic loads for all the directions of the building.

The Earthquake Loads which needs to be added in Load Patterns are Eqx, Eqx-, Eqx+, Eqy, Eqy-, Eqy+.

To Define the Load Patterns click and select Define < Load Patterns to open Define Load Pattern Tab.

From the Opened Tab, Add New Loads such as

Dead Load (Default) = Dead, 1, None.

Live Load = Live, 0, None.

BrickWall = Super Dead, 0, None.

Finishes = Super Dead, 0, None.

Eqx = Seismic, 0, lS 1893 2016.

Eqx- = Seismic, 0, lS 1893 2016.

Eqx+ = Seismic, 0, lS 1893 2016.

Eqy = Seismic, 0, lS 1893 2016.

Eqy- = Seismic, 0, lS 1893 2016.

Eqy+ = Seismic, 0, lS 1893 2016.

Then We should change the Direction and Eccentricity for all the Earthquake loads created as per their directions of Seismic forces.

First Select Seismic Load Eqx and click Modify/Lateral Load to open Indian IS 1893-2016 Seismic Loading Tab.

From the opened tab, click the Check box of X Dir and unclick all the other check box below Direction and Eccentricity at let the other values as default.

And click User Defined option below the Time Period, then Input the Calculated Time period Ta = 0.66 sec and click OK.

Second Select Seismic Load Eqx+ and click Modify/Lateral Load to open Indian IS 1893-2016 Seismic Loading Tab.

From the opened tab, click the Check box of X Dir + Eccentricity and unclick all the other check box below Direction and Eccentricity at let the other values as default.

And click User Defined option below the Time Period, then Input the Calculated Time period Ta = 0.66 sec and click OK.

Second Select Seismic Load Eqx- and click Modify/Lateral Load to open Indian IS 1893-2016 Seismic Loading Tab.

From the opened tab, click the Check box of X Dir - Eccentricity and unclick all the other check box below Direction and Eccentricity at let the other values as default.

And click User Defined option below the Time Period, then Input the Calculated Time period Ta = 0.66 sec and click OK.

Second Select Seismic Load Eqy and click Modify/Lateral Load to open Indian IS 1893-2016 Seismic Loading Tab.

From the opened tab, click the Check box of Y Dir and unclick all the other check box below Direction and Eccentricity at let the other values as default.

And click User Defined option below the Time Period, then Input the Calculated Time period Ta = 0.66 sec and click OK.

Second Select Seismic Load Eqy+ and click Modify/Lateral Load to open Indian IS 1893-2016 Seismic Loading Tab.

From the opened tab, click the Check box of Y Dir + Eccentricity and unclick all the other check box below Direction and Eccentricity at let the other values as default.

And click User Defined option below the Time Period, then Input the Calculated Time period Ta = 0.66 sec and click OK.

Second Select Seismic Load Eqy- and click Modify/Lateral Load to open Indian IS 1893-2016 Seismic Loading Tab.

From the opened tab, click the Check box of Y Dir - Eccentricity and unclick all the other check box below Direction and Eccentricity at let the other values as default.

And click User Defined option below the Time Period, then Input the Calculated Time period Ta = 0.66 sec and click OK.

Then we should check the Load cases whether the created Loads are added in the model or not.

To open it click and select Define < Load Cases to open a Load Cases Tab.

From the opened Load Cases Tab, check all the created loads are defined and click OK.

Then the Loads in Mass Source should be added.

For that click and Select Define < Mass Source to open the Mass Source Tab.

In the opened Tab, Click Modify/Show Mass Source option to open The Mass Source Data Tab.

Then from the opened Mass Source Data Tab, Click the check box of Specified Load Patterns below the Mass Source and Unclick all the other CheckBoxes.

Followed by Add Load patterns and Multipliers as Dead = 1, BrickWall = 1, Finishes = 1, Live = 0.25 and click OK.

Then we should assign the Center of gravity (DIAPHRAGM) to all the Floor/Slab.

For that Select all the Drawn Slabs by clicking and selecting Select < select < properties < Slab Sections < S150 and click Select to select all the assigned Slabs.

Then to assign Diaphragm click and select Assign < Shell < Diaphragm to open a Shell Assignment - Diaphragms Tab.

After opening of the Tab, Select D1 and click Apply to assign the Diaphram to all the slabs.

After Assigning the Diaphragm, we should Assign a Pier Lables to all the Shear Wall before Running analysis.

For that Click and Select Assign < Shell < Pier Label to open a Shell Assignment - Pier Label Tab.

Before Start assigning the Pier Labels, we should make sure whether Editable Stories are changed as All Stories.

After opening of the Shell Assignment - Pier Label Tab, click Modify/Show Definitions and Add number of Labels as equal as Shear Walls created.

Then click and select the Shear Walls one by one to assign the Suitable Pier Lable to them by clicking Apply.

Also we should make sure to Set Load Cases to Run before Start to Run Analysis.

For that Click and Select Analyse < Set Load Cases to Run to open Set Load Cases to Run Tab.

After opening of the Tab, check whether the Action = Run for All Cases.

And make sure to click the check box of Calculate Diaphragm Centers of Rigidity and click OK.

Then we can Check whether the created model has generated any Warning Messages.

To check that Click and Select Analyze < Check Model to open a Warning Tab.

From the opened Warning Tab, we can see that the Model has been checked. No warning messages were generated.

So the created model were ready to Run the analysis.

Before Start Running the Analysis, the Response spectrum should be defined as per IS Code 1893 2016.

For that Click and Select Define < Functions < Response Spectrum to open Define Response Spectrum Functions Tab.

From the opened Tab, Select IS 1893 2016 below the Choose function Type to Add and click OK.

Then the Response Spectrum Function Definition - IS 1893 2016 Tab will be open, here make the appropriate Parameters.

Here change Function Name = Func_IS 1893, Parameters < Seismic Zone = V, Seismic Zone Factor Z = 0.36, Importance Factor I = 1, Soil Type = II, Response Reduction Factor R = 5 and click OK.

Followed by we should Add New Case Load for the Response Spectrum Load in both X and Y directions in Load Case Data.

For that click and select Define < Load Cases to open Load Cases Tab.

From the opened Tab, click and Select Add New Case to open Load Case Data Tab to Apply Load for Response Spectrum in X direction.

In the opened Load Case Data Tab, Change Load Case Name = RSx, Load Case Type = Response Spectrum.

And in Load Applied < Load Type = Acceleration, Load Name = U1, Function = Func_1893, Scale Factor as Default and click OK.

Likewise to Apply Load for Response Spectrum in Y direction click and Select Add New Case to open Load Case Data Tab

Then in the opened Load Case Data Tab, Change Load Case Name = RSy, Load Case Type = Response Spectrum.

And in Load Applied < Load Type = Acceleration, Load Name = U2, Function = Func_1893, Scale Factor as Default and click OK.

Atlast we should Define the Load combinations for the Added Loads.

For that click and select Define < Load combination to open Load combinations Tab.

From the opened Tab, Click Add Default Design Combos to open Add Default Design Combinations Tab.

Here in opened Tab, click the Check Boxes of Concrete Frame Design and Concrete Shear wall Design and click OK.

After clickin OK, we can see the Load Combinations of All loads are combined and added.

Now we can Run Analysis of the Model created to see the Deformed Shapes and Base Reaction by the Loads Applied.

To Run the Analysis, Click the Tool present at the Toolbar menu at the Top of the workspace names Run Analysis (F5).

Here, we can see the Deformed shapes of the building model after Running the Analysis.

Now we can see the Base Reaction values of the Building Model from the Analysis Result Table.

To open the Analysis Result Table, Click and Select Display < Show Table to open Choose Tables for Display Tab.

After opening of the Tab, Click and Select Analysis Result < Structure Output < Base Response < Table Base Reactions.

From the opened Tab, we can see Result of all the Base Reaction of the building model.

Here we can see that for Eqx, Eqx+, Eqx- the FX = 3559.4142 kN and for Eqy, Eqy+, Eqy- the FY = 3559.4142 kN.

But the values for RSx and RSy did not has the values near the values of Earthquake forces in all directions.

To make the Response spectrum forces as equal to the Earthquake forces we should change the appropriate Scale factor for both RSx and RSy.

For that Click and Select Define < Load Cases to open Load cases Tab .

From the opened Tab, click RSx and Select Modify/Show Case to open Load case Data.

In opened Tab, Edit the Scale factor we calculated below.

RSx = 1937

Eqx = 3559

SFx2 = Eqx/RSx (SFx1)

SFx2 = 3559/1937 (9806.65)

SFx2 = (1.837) 9806.65

SFx2 = 18018.51

Likewise for RSy, click RSy and Select Modify/Show Case to open Load case Data.

In opened Tab, Edit the Scale factor we calculated below.

RSy = 2139

Eqy = 3559

SFy2 = Eqy/RSy (SFy1)

SFy2 = 3559/2139 (9806.65)

SFy2 = (1.663) 9806.65

SFy2 = 16316.90

Then again click and Run the Analysis of the Building model with edited Scale Factor.

After the Analysis of the model we can see the Table of the Analysed Result .

To open the Table click and Select Display < Show Tables.

Then the Choose Tables for Display Tab will open, there click and select Analysis Results < Structural Output < Base Reaction.

Then the Base Reaction Tab will open, here we can see the Response spectrum Load values are almost equal to the Earthquake Load Values in Base Reaction.

Now we can see that the structural model we have designed and analysed meets structural code requirements without compromising architectural functions.

Then we can see the Table of Model Participating Model ratios by click and selecting Display < Show Tables to open Choose Tables for Display.

From the opened Tab, click and select Analysis Results < Structure Output < Modal information < Table Modal Paricipating Mass Ratios.

Then the Modal paricipating mass Ratios Tab will open, we can see the Mass ratios for all the Modals in all directions.

To see the Maximum story drifts of the earthquake forces such as Eqx and Eqy we should open Story Reponse Tab.

For that click and select Display < Story Response Plots to open Story Reponse Tab.

After opening of the Story Response Tab, change Display Type = Max Story Drifts and Case Combo = Eqx to see the Maximum Story Drifts of the earthquake load force at the X direction.

And here it was below 4. So it is safe.

Likewise to see earthquake load force at the X direction, change Display Type = Max Story Drifts and Case Combo = Eqx to see the Maximum Story Drifts.

And here it was below 4. So it is safe.

RESULT :

Data required :

Pinned support, Base + 9 Story (Ground terrace) + 1 Mumty.

Column 450mm x 600mm, beam 400mm x 500 , Slab 150mm thick, shear wall 300mm thick.

Live load 2.5 KN/m^2, Floor finish 1.5 kN/m, Wall load 5kN/m , Water tank 20K liter over mumty equivalent to 200 KN overall load.

Conceptual design considerations before analysis :

Re-entrant and cutout check & modification (compromise)

Vertical irregularity (soft story)

Planar irregularity (Looks symetrical)

2% shear wall area with respect to building area (8m^2)

Stiffness modifier for column, beam and shear wall (0.35 for beam, 0.7 for vertical)

Key points to remember while modelling :

No slab, No wall load in ground floor.

Proper end releases in beam.

No interior wall load in terrace.

Comparison on static and dynamic forces and revising the factor.

Checks after analysis :

Model mass analysis for first 3 modes dominates at least 65% (Achieved for x-axis only)

Mode-1 and Mode-2 differs by 10% (Achieved)

Principle modes be greater than Torsional model (Achieved)

Inter story drift ratio limited to 0.004 (Achieved)

Axial stress in column and shear wall (Achieved)

Base shear share between shear wall & columns (Not dual systems)

Structural Modelling using Etabs 2018

Ship work like this
in your own course.

Talk to a career counsellor

Ship work like thisin your own course.

Talk to a career counsellor

Ship work like this
in your own course.