Structural Modelling using Etabs 2018

PROCEDURE:

STEP: 1

• First open the etabs software.

• Next click on the file option at the left side top corner and select the new model, as shown below.

• After selecting the new model the new tab opens, in that tab we have to select 'Use Built-in Settings with option, as shown below.

• After setting the model Initialization the templates tab will opens and, select the Grid only and press ok.

• Next we need to do the settings in Grid system data, as shown below.

• Next we need to add the stories upto 7 story in the Story Data, as shown below
• The 7 stories are added in the Story Data, as shown below.

Step: 2

• Next the plan views are visible in the etabs screen, as shown below.
• also open the 3D view

Step 3

Now go to file option and save the project as shown below.

STEP: 4

• Next we need to define option and select material properties, as shown below
• After selecting the material properties the new tab appears, then we add new materials by selecting the Add new material option, as shown below.

STEP: 5

• Now we need to add material type as concrete and grade as M25.

• so, go to define< material properties < add new material < india< concrete < indian < M25

• Next we need to check the material property data, as shown below.

STEP: 6

• Now we need to add new material type as rebar and grade as HYSD Grade 415.
• Next we need to check the material property data, as shown below.

• Now we need to add new material type as rebar and grade as HYSD Grade 500
• Next we need to check the material property data, as shown below.

STEP: 7

• Now, go to defint < section properties < frame sec tion < add new ... as shown below.

• After selecting the Add New Property, the new tab appears.
• In that new tab we select the Rectangular shape type in concrete.

• Next the frame section property data will be visible.

• In that we add beam size as BEAM250x450, change the material
• Next we need to select the Modify/Show Rebar option as shown below.
• After selecting the Modify/Show Rebiar option the new tab appears, in that we select the design type as M3 Design only (Bearn)
• Next we select longitudinal bars with the grade of HYSD500
• Next we select Confinement bars with the grade of HYSD415

• Similarly, add new material < select Rectangular shape type in concrete, as shown below
• Next the frame section property data will be visible, In that we add column size as BEAM300x500, as shown below.
• Next we need to select the Modify/Show Rebar option as shown below.
• After selecting the Modify/Show Rebar option the new tab appears.
• In that we select the design type as M3 Design only (Bearn).
• Next we select longitudinal bars with the grade of HYSD500
• Next we select Confinement bars with the grade of HYSD415

STEP: 8

[REPEAT SAME STEPS AS USED IN CASE OF BEAM]

• we have to add the column size as 400x600 in the frame section property data, as shown below.
• (Note: to specify the dircetion of column accordingly as shwo in given plan)

STEP: 9

• Next FOR slab section from section properties
• go to defint < section properties < SLAB section < add new ... as shown below.

• Next the slab properties tab will be vissible.
• In that we select the Modify/Show Property option, as shown below
• After selecting the Modify/Show Property option, the new tab appears.
• In that we need to put the slab name as Slab 125, it means slab with the thickness of 125mm.

• And we take the concrete grade as M25, as shown below.
• Next we have to click the ok option..

SIMILLARLY,

• Now we take the slab thickness seperately for staircase with the thickness of 200 mm

STEP : 10

• go to defint < section properties < wall section < add new ... as shown below.
• Next we have add the wall properties in the wall property data

STEP: 11

• Next we need to add the columns using the quick draw column option as shown below.

• Next we need to add the beams using quick draw tool

• Next we need to add the secondary beams using the quick draw beams option

• Next we add the shear walls in required location in the residential building

• Next we need to add the slab using quick draw floor/wall option

STEP: 11

• Now we go to the base plan and select all base joints.
• Next we select the Restraints from joint option, as shown below.

• Now we need to select the fixed joint and click on apply and then click on close button, as shown below.

STEP: 12

• Next we need to select the load patterns from the define option, as shown below.

• Now we should add Dead load, live load, Brickwall load, and earthquake load, as shown below.

STEP: 13

• Next we need to select the distributed load from the frame loads, as shown below.

• Then after the new tab will appear, In that we select load pattern as Brickwall, and we take uniform load as 3 kN/m and then click on the apply button and close.

STEP: 14

• Next we have to click on the assign option and then select shell loads, from the shell loads we select the Uniform option, as shown below.

• Here we apply the live load for the staircase portion, varanda, and lift core area.

• Next we apply the live load for the remaining portions in the residential building, as shown below.

STEP: 15

• Next we have to select live load reduction factors from the design option, as shown below.

• Now we add the reduction factor by decreasing 10% from 1st floor to 7th floor as shown below

STEP: 16

• Next, from the define option we select the mass source, as shown below.

• Next we add the load patterns in the Mass Source Data, as shown below.

STEP: 17

• In the select option we select object type option, as shown below.

• After selecting the object type option, the new tab will be visible. In that select the floors and click on the select button and close

• Next we have to select the Diaphragms from the shell option, as shown below

• After selecting the diaphragms the new tab will appear, in that select D1 and click on the apply button and close

STEP: 18

• Next we have to select the Pier label from the shell option, as shown below

• Before going to the shear wall design we have to assign the names for the shear walls(PLP2 P3 P4 P5 P6 P7) as shown

STEP: 19

• Next, from the define option we select the load combinations, as shown below.

• After selecting the load combinations the new tab is visible, In that we select Add Default Design Combos option.

• Next we select "concrete frame design & concrete shear wall design in the Add Default Design Combinations as shown below

• Now we can see here that the load combinations are visible, as shown below.

STEP: 20

• Next we select the Modal cases from the Define option, as shown below
• After selecting the Modal cases the new tab is visible. In that we give modal case name as Modal 1 & we give the maximum number of modes as 20, as shown below.

STEP: 21

• Next we have to check the model by clicking the check model option as shown below

• After the model is checked, then the warning tab will be visible and it tells that there is no warning messages, as shown below

STEP: 22

• Now we select the Response spectrum from the Functions from define option, as shown below

• After selecting the Respnse spectrum the new tab is visible, in that we choose IS 1893 2016 from the Choose function type and click on the Modify/Show spectrum option, as shown below

• After selecting the modifyshow spectrum option the new tab will be visible. In that we give the Function name as 15 FUNCTION and remaining details will be set by the software itself we don't need to change any of the details in that response spectrum function tab as shown below

STEP: 23

• Next we have to select the Load cases from the Define option, as shown below.

• Next the Load cases tab will be visible, In that we select the Add new case as shown below

• Now we have to enter the details of load case in the load case data as shown below

Now we have to do the run analysis

STEP: 24

• Next, from the display option we select the show tables option, as shown below.

• After selecting the show tables option the new tab will be visible.
• Now we select the Base Reactions and click on the ok button, as shown below.

• The Base Reactions table will be visible, as shown.

• Here we have to check that EQ should be closer to the RS. to get the closer to each other we should calculate that [(EQ/RS) * Scale factor of Response spectrum.]
• After we enter these values for response spectrum as scale factors at X and Y directions in load case data, then the EQ is closer to the RS from the base reaction table, as shown below

STEP: 25

• Next, from the display option we select the show tables option, as shown below.

• After selecting the show tables option the new tab will be visible. . Now we select the Modal Participating Mass Ratios and click on the ok button, as shown below.

• Now the Modal Parbopating Mass Ratos table will be visible, as shown below

STEP: 26

• Next we select the Story response plots from the Display option, as shown below.

• The story response for max story drift at X and Y direction, should not be more than 4%

STEP: 27

• Next we open the select plan view tab and select the base floor, as shown below

• Next we have to open the reactions tab, then we select the eartquake load towards X-direction(EQX) in the load case, then click on the ok buttion as shown below

• Now the base shear reactions will appear, as shown below.
• When we divide the base shear taken up by the shear wall divided by the total base shear of building will get the % of the shea forces taken up by the shear wall
• And if that is less than 80%, then the more shear walls we need to add to the structure