Structural Modelling using Etabs 2018

Aim : To analysis a G+7 building with th same floor plan through out the levels. The structural model must comply with provisions of IS 1893 and IS 13920. To Run a modal response spectrum analysis and check analysis results of the etabs model for inter-storey drift requirements, vertical & planar irregularities, minimum shear wall requirements,maximum axial load ratio for column and shear walls, effective moment of inertia for beams
and columns etc.

Procedure : Download the given attachement of the building plans.

step1 :Open etabs software . Give Indian IS codes as default. Customise the grid in x direction and y direction. Give storey as 9 since its a g+7 and we are considering plinth seperately and as well the top most terrace seperately as a level.

Step 2: Once the basic is done.Next the plan views are visible in the ETABS screen,as shown below.
Next we need to open the 3d-view ,as shown in the below figure.

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Step 3: Next we need to define option and select material properties.After selcting the material properties the new tab appears,then we add new materials by selecting the add new material 

STEP(4):-Now we need to add material type as concrete and grade as M25.
Next we need to check the material property data.

STEP(5):-
Now we need to add new materials type as rebar and grade as HYSD Grade 415.
Next we need to check the material property data .

Step 6: 

STEP(7):- Now we need to select the section properties and click on the frame sections below.

STEP(8):-After selcting the frame sections the new tab will be visible ,in that we need to select the Add New Property,as shown below. After selcting the Add New Property ,the new tab appears .
In that new tab we select the rectangular type shape in concrete ,as shown below.
Next the frame sction property data will be visibke ,in that we add beam size as B250x450 ,as sown below.
Next we need to select the modify /show rebar option as shown below.
After selcting the modify/show rabar option the new tab appears,in that we select the design type as M3 design only(Beam).
Next we select longitudinal bars with the grade of HYSd 500.
Next we selct confinement bars with the grade of HYsd 415.
Again we have to 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 B 300x500,as shown below.
Next we need to selct the Modify/swhiw 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(Beam).
Next we select longitudinal bars with the grade of HYSD500.
Next we select confinement bars with the grade of HYSD415.

STEP(9):-
Next we have to add the column sizze as 450X350 in the frame section property data ,as shown below.
Again we have to add the another column size as 400x600 in the frame section property data,as showm below.

STEP(10):-
Next we selct the slab option from the section properties ,as shown below.
Next the slab properties tab will be visible,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 menas slab with the thickness of 125mm.
Next we have to click the ok option.
Now we take the slab thickness separartely for staircase with the thickness of 200mm,as shown below.

STEP(11):-
Next we have to add the wall properties in the wall property data,as shown below.

STEP(12):-
Next we need to add the columns using the quick draw columns option,as shown below.

STEP(13):-
Next we need to add the beams using the quick draw beams option,as shown below.

STEP(14):-
Next we need to add the secondary beams using the quick draw beams option,as shown below.

STEP(15):-
Next we add the shear walls in required locations in the residential building ,as shown below.

STEP(16):-
Next we need to add the slabs using the quick draw floor/wall option,as shown below.

STEP(17):-
Now we go to the base plan and select all base joints.
Next we select the restrains 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 shownbelow.

STEP(18):-
Next we need to select the load patterns from the define option,as shown below.
Now we should add dead load ,live load ,Brick wall load , and earthquake load ,as shown below.

STEP(19):-
Next we need to select the distributed load from the frame loads ,as shown below.
Then after the new tab will appears ,in that we select load patterns as brickwall,and we take uniform load as 3.5KN/m and then click on the apply button and close.

STEP(20):-
Next we have to click on the assign option and then selct shell loads from the shell loads we select the uniform option,as shown below.
Here we apply the 3KN/m2 live load for the staircase option,varanda,and lift core area.
Next we apply the 2KN/m2 live load for the remaining portions in the residential building ,as shown below.

STEP(21):-
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(22):-
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 belwo.

STEP(23):-
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 om the select button and close.
Next we have to select the diaphrams from the shell option,as shown below.
After selecting the diaphrams the new tab will appears,in that select D1 and click on the apply Button and close.

STEP(24):-
Next we have to select the pier lable from the shell option,as shown below.
Before goning to the shear wall design we have to assign the names for the shear walls (P1,P2,P3,P4,P5,P5,P6,P7,P8,P9),as shown below.

STEP(25):-
Next from the define option we select the load combinations ,as shown below.
Aftert 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(26):-
Next we select the modal cases from the Define option,as shown below.
After selecting themodal cases the new tab is visible,in that we give modal case name as modal1& we give the maximum number of modes as 20 ,as shown below.

STEP(27):-
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 message ,as shown below.

STEP(28):-
Now we select the response spectrum from the functions from define option,as shown below.
After selecting the response spectrum thenew 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 modify/show spectrum option the new tab will be visible ,in that we give the function name as IS FUNCTION and remaining details
will be set by the software itself,we don't need to change any of the details in that response function tab ,as shown below.

STEP(29):-
Next we have to selct the load cases from the define option,as shown below.
Next the load cases taab 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 ,as shown below.

STEP(30):-
Next from the display option we select the show tables option ,as shown below.
After selcting 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.
Next the bae reactions table will be visible,as shown below.
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)X scale fasctor of response
spectrum.
Now substituting the values from the table,as X-direction(284406348/900.7656)X(9806.65),at Y-direction (2844.6348/1002.1982)X 9806.65.
At X- direction we get,30969.6.
At Y- direction we get ,27835.15.
We put the above values as scale factor for response spectrum at X and Y directions in the load case data.
After we enter these values for response specrtrum as scale factors at X and Y directio0ns in load case data, then the EQ is closer to the RS from the bas
reaction table,as shown below.

STEP(31):-
Next from the display option we select the show tabbles 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 click on the ok button ,as shown below.
Now the modal participating mass ratios table will be visible,as shown below.

STEP(32):-
Next we select the story respoonse plots from the display option ,as shown below.
The story response for maximun story drifts at X & Y directions should not be more than 4%.

STEP(33):-
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 earthquake load towards X-direction(EQX) in the load case,then click on the ok button asshown below.
Now the base shear reactions will mappears,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 shear 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. 

RESULT : THE G+7 BUILDING IS ANALYSED IN ETBAS SOFTWARE AS PER THE I.S .CODES