Modelling of 25 storey building with the specified properties using ETABS

AIM:- to model the 25 story building using E-tabs

GIVEN DATA

• 
• size of the beam 300x400mm
• size of the column 800x800mm
• the thickness of the slab is 150mm
• grade of concrete M30
• grade of steel Fe415
• dead load on beams from infill walls is assumed as 10KN/M
• live load on the floor is taken as 3 KN/M^2

STEP 1: to modify grid and story data

• open E-tabs
• Click on the new model
• select the codal provisions of steel and concrete

• then go custom grid spacing
• then edit grid data

• Click on a custom story data
• edit the height of the story
• add additional story required

STEP 2:- to define material properties and section properties

• go to define> material properties
• add reinforcement and concrete grades

• then go to define
• Click on section properties>frame sections
• then add beam and columns parameters and material

• go to define
• Click on section properties > slab sections
• modify the parameter of the slab and add material

STEP 3:- to define loads and load combinations as given in the question

• go to define
• select load patterns
• add the type of loads the structure is subjected to

• after adding the load patterns
• modify the properties of the seismic loads
• assume seismic zone as 2
• influence factor as 1
• response reduction factor R as 5

• then add the mass source
• go to define> select mass source

• then add load combinations
• go to define> load combinations
• click on add design loads
• select on concrete frame design

STEP 4:- modeling the structure

• add beams, columns and slabs to the model
• go to modeling
• select the column from the properties browser
• the add the columns at the desired locations

• similarly add beams and slab

STEP 5:- to assign loads to the structure

• to assign wall load on beams
• go to select>properties
• Click on frame selections and select all beams
• then go to assign
• frame loads> distributed
• modify the load and click on apply

• then select all slab sections
• go to assign
• click on shell> diaphram
• select D1 and click on apply

• then to assign live load
• go to select >properties>slab sections
• select all the slabs
• go to assign
• shell loads> uniform loads
• give the input as 3kn/m^2
• then click on apply OK

• after assigning the loads
• click on run analysis

RESULTS:-

• the translation natural period T1=5.536
• the translation natural period T2=5.313

• achieved 80% of the modal participating mass ratio at mode point 1 and 2