Project 1 - MODELLING, ANALYSIS & DESIGN OF TALL BUILDINGS IN ETABS

AIM:

To analysis & design of a state-of-the-art tall building using ETABS software.

SOLUTION:

• Open New Model in ETABS and Set the unit to metric SI as per Indian Standard as shown below:

• Customise the grid system data and story data and press OK, as shown below:

• Go to Define tab, then Material Properties and Add New property, then Give material type as concrete and Grade as M30 And steel and grade as HYSD 415, as shown below:

• Go to Define tab, then Section Properties and Frame Sections finaly Add New Property and Add Column 1000 x 1000 and Beam 750 x 1000, as shown below:

• Go to Define tab again and here Section Properties, then Slab Sections and Add New Property and Add Slab 150, as shown below:

• Again Go to Define tab, Section Properties, then wall Sections and Add New Property and Add shear wall 250, as shown below:

• Now Place Columns, beams, slabs and walls as per the architectural drawing
• Then Go to Edit tab, Replicate and story and select the story to be replicated and apply
• As shown below:

• Go to base and select all the joints
• Then Go to assign tab, joint restaints and select fixed support for all the directions and click on apply
• As shown below:

• Now Go to define tab and Load Patterns and add Dead, Live, Earthquake and Wind Load, as shown below:

• Then Go to define tab and Load Combinations and Add default design combos, then Concrete frame design, as shown below:

• Go to define tab, then Mass source and Modify Mass Source, as shown below:

• Now Go to define tab and P-Delta options
• Then Go to Assign Tab and Frame Loads and Distributed Load and assign the load to the beams
• As shown below:

• Now Go to Select tab, Properties and Slab sections and Select slab 150
• Also Go to Assign Tab, Shell Loads and Distributed Load and assign the load to the Slabs
• Then Go to Select tab, Select and Object Type and Floor
• As shown below:

• Once done Go to Assign tab, Shell, diaphragms and D1
• Then Go to Analyze tab and Check model and insame tab go for Ran Analysis
• As shown below:

• Now select reactions tab and select earthquake load toward x direction in the load case and click ok. Now base shear reaction will appear

Slab thickness = 150mm

Beam size= 300mm X 300mm

Live load = 2 KN/m2

Floor finish= 1.5 KN.m2

Brickwall load= 3.5 KN/m

Self weight of slab = 0.150 X 25 KN/m2 = 3.75 KN/m2

Total load in slab = 3.75 + 2 + 1.5 = 7.25 KN/m2

Load in each end of B1:

Area 2(Trapezoidal area)

A1 = 1/2 * (1.529 + 4.587) * 2.5 = 7.645 m2

Bay width of B2 = A1/L or L/4 = 7.645/4.587 = 1.66 m or 1.14m

UDL transferred from slab-1 to Beam-2 = B.W X Slab-2 load = 1.66 X 7.25 = 12.035 KN/m

Beam-1 Self weight = 0.4*0.4*25 = 4 KN/m2

Total UDL on B1 = 4 + 12.035 + 3.5 = 19.535 KN/m

Total load on B1 = (19.535 X 4.857) = 89.607 KN

Load on each end for B1 is 44.804 KN

Load in each end of B2:

Area 2(Triangular area)

A2 = [1/2 * 2.5 * 1.529 ]* 2 = 3.82 m2

Bay width of B2 = A2/L or L/4 = 3.82/5 = 0.764 m or 1.25m

UDL transferred from slab-2 to Beam-2 = B.W X Slab-2 load = 1.25 X 7.25 = 9.0625 KN/m

Beam-1 Self weight = 0.4*0.4*25 = 4 KN/m2

Total UDL on B2 = 4 + 9.0625 + 3.5 = 16.5625 KN/m

Total load on B2 = (16.5625 X 5) = 82.82 KN

Load on each beam B2= 41.41 KN

Total axial load on column C1 = 44.804 + 41.41 = 86.21 KN

Total axial load on C1 column = Number of floor X Load in first floor Column C1 = 15 X 86.21 = 1293.15 KN

Now we have almost got that same result from ETAB sodtware analysis= 1309.87 KN

RESULT:

• Manual calculations for the base reactions in gravity load cases
• Submit ETABS model with the complete model of the tall building (exported .e2k format, do not attach .EDB format directly)
• The model should pass all design and serviceability requirements.
• A comprehensive project report from the ETABS software (as PDF file)