Modelling of 25 storey building with the specified properties using ETABS

Modelling of 25 storey building with the specified properties using ETABS

 

 

Model a 25 storey building on ETABS with structural properties as specified below. Ground floor or plinth floor level can be taken at a height of 1.5 metres from the base. Each of the successive 25 storeys has a storey height of 3 metres.

Structural Element Sizes 

• Beams : 300 × 400 mm 
• Columns : 800 × 800 mm 
• Slab : 150 mm thick 

Material Properties 

• Grade of Concrete : M30 
• Grade of Steel Reinforcement Bars : Fe 415 

Loading 

• Dead Load on beams from infill wall : 10 kN/m (Let us assume the same for roof floor in view of parapet)
• Live load on floor : 3 kN/m2 (Let us assume the same for roof floor)

a) Buildings are assumed to be pinned at the base

b) All columns in all storey are of the same size

c) All beams in all storeys are of the same size

d) Building is located on Soil type-II and in Zone-III. Assume other factors if required.

 

Carry out the following exercises:

• Check if the translational fundamental natural period of vibration in both the x and y direction is approximately: $T_{x1}$= 4.4 second $T_{y1}$= 4.2 second

This check will help confirm if modelling is done correctly. Some deviations from the above values is possible (± 2%). But any major deviation will suggest an error in modelling. 

• Check if the following provision in Table 5 of IS 1893 (part 1) – 2016, on torsional irregularity satisfied:

The natural period corresponding to the torsional mode of oscillation must be less than the two fundamental translational modes of oscillation along each principal plan directions.

• Check if the two provisions of clause 7 in Table 6 (shown below) of IS 1893 (part 1) – 2016, regarding vertical irregularity is satisfied

 

• Check if provision on inter-storey drift limitations in clause 7.11.1.1 satisfied. Please note that this check is for Serviceability Limit State and hence is for situation when stucture is subjected to unfactored seismic base shear

 

AIM: To know the modeling of a high rise building in ETABS software

 

Introduction: modeling the 25 storey building with etabs and use special property on etabs with applying load and check as per IS 1893(part1)-2016

 

Procedure:

step 1) just open etabs software 

          

 

then click on new model and choose use buit-in setting with option 

 after that choose proper option from given and press ok 

 

then click on custom grid spacing 

and edit the setting by clicking on edit grid data 

 

go to grid system data 

edit by adding grid and define X ordinate distance and Y ordinate distance 

and then press ok 

 

step 2)

then go for custom storey data 

so select custom storey option from given 

edit the setting by adding 25 storey 

and press ok 

 

step 3) 

now our basic model is ready 

 

then define material 

so just go on define option on ribbon 

and choose material option from that 

 

and click on add new material property 

 

then click on Ok 

 

then, also add fe415 steel proprty 

so go to add new material 

select steel otion and press ok 

 

our material proprty is added successfully 

 

step 4) 

now go for section property 

from define option 

and select frame option from that 

 

fill all detail and modify modifiers and rebar

 

same work for column 

go to frame section select rectangle section 

 

step 5) go for slab defination 

 

click on add new property 

fill all data and press ok 

 

 

step 6) then go for load patterns 

\

add wall load and type as super dead load 

 

also modify earthquake load from modify option 

 

then add and modify EQX and EQY lateral force 

 

 

step 7) mass sources 

           put load value according to load 

 

 

step 8) check for load case 

go to define 

and click on load case option from list 

check all and press ok if all correct 

 

 

step 9) load combination 

go to load combination from define

 

 

step 10) modeling stage 

draw column by clicking on draw column option 

 

now set working plane as all storey, cause column for all stories 

and column on grids like that 

 

we can also use replicate option for draw column 

 

 

step 11) now same do for Beams 

go to frame draw 

select beam property as 300X400mm

and draw on overall 

 

 

step 12) slab 

so go for storey one it is master storey 

go to draw floor option

select working plane as similar storey 

then choose slab property as S150

and draw the slab on floor 

like that to all grids 

 

 

 

step 13) assign frame load 

go to select option and select all the beams 

then go to assign and frame load assignment ( distrubuted loads ) 

 

same assign load on slab 

same process done for slab and assign 3KN/m for all slab 

 

 

then select slab again and assign diaphragm 

select D1 and press ok 

 

 

 

 

step 15) now analyse the model 

go to run analyse and click on it 

then save the file 

 

 

Result: