Structural Modelling using Etabs 2018
Data required for ETABS analysis
- Pinned support, Base + 9 story (ground to terrace)+ 1 mumty
- Assume Column 450mm x 600mm, Beam 400mm x 500mm, Slab 150mm thick, Shear wall 300mm thick.
- Live load 2.5 KN/m^2, Floor finish 1.5 KN/m^2, Wall load 5 KN/m, Water tank 20k litre over mumty equivalent to 200 KN overall load.
Conceptual design considerations before analysis
- Re-entrant and cutout check & modification (Compromise)
- Vertical irregularity (soft story)
- Planar irregularity (looks symmetrical)
- 2% shear wall area with respect to building area (8 m^2)
- Stiffness modifier for column, Beam & shear wall (0.35 for beam, 0.7 for vertical)
Checks after analysis
- Modal mass participation for first 3 modes dominates at least 65% (Achieved for X-axis only)
- Mode-1 and Mode-2 differ by 10% (Achieved)
- Principal modes be greater than torsional mode (Achieved)
- Inter story drift ratio limited to 0.004 (Achieved)
- Axial stress in column and shear wall (Achieved)
- Base shear share between shear wall & columns (Not dual system)