Challenge

Concept on positioning of Columns

Symmetry: -

The Given Layout of the Framing Plan is Symmetric. it’s a Symmetrical well Distributed in Plan Layout structural Elements is Appropriate to achieve Uniformity.
This Tends to Reduce the Horizontal Displacements in both two horizontal displacements in both two orthogonal horizontal directions
Its also has a very good Uniformity also

Redundancy: -

There are missing Structural elements in the Periphery of the plan, this causes the uneven distribution of earthquake action effects in non linear rage across the plan. The energy dissipation across the structure is very low which results in nonreliable structure

Bi Directional Stiffness: -

The Building Plan may not be able to resist the horizontal seismic actions in the shorter direction (Y-axis) also the resistance and stiffness in the shorter direction (Y-axis) in less When Compared to Longer Direction (x-axis)

Ductility: -

The Building may not be able resist the elastic earthquake forces in shorter direction (Y-axis) also it may result inelastic Response. The Reduction in Design Force in the shorter Direction (Y-axis) is to be Compensated by Ductility.

Different Irregularities that could be considered are as follows.

Soft Storeys: -

Its necessary to Provide the height of the soft storeys equal to the height of the other storeys
Its observed, the height of the soft storeys is more then the floors above it because of which its possible that the stresses would make the height of all the storeys equal considering seismic analysis, and the eccentricity is also more for the columns at the bottom floor.

Mass Irregularity: -

The Open story also causes mass irregularity in the building because the high mass concentration is present above the Open floor. That is Upper floors carry more mass than the open floor
Also the No.of Floors are Higher above this open Floor

Vertical Geometrical Irregularity: -

There is a Change with the horizontal dimensions of lateral force resisting due to the open storey in mid height and also the vertical geometry of the building which means the length of the top storeys are varying along the building unit.
This Causes the Effects in the Building which needs to be decoupled by providing shear walls or decoupled moments
The flexibility provided due to the variation need to be compensated by providing ductility
As an engineer refer the 1893 Is Code Before designing

Open GF: -

The Ground floor of the building is Open, which may be a Soft Storey Due to this the GF Excitation the columns could have been unable to resist the earthquake and form collapse
This is called as soft storey mechanism

Two Short Sides of the Perimeter in Filled: -

The Mass has been undistributed in all the sides of the building in all storeys because it is given that the two sides of the perimeter of the building is in filled, which causes the irregular distribution of mass called as mass irregularity
This can be avoided by providing the shear walls in the direction of two short sides of the perimeter which can resist the lateral loads by providing stiffness in the building frame and helps to resist the earthquake actions
Adjust the mass irregularity for the plan

Left Hand Bay Staircase Filled with Concrete: -

The Extreme Left-hand Bay has staircase due to this mass go concentrated in the staircase area due to which torsional effects are formed having the base of the concentration of mass in the Staircase
To avoid this type of Failure the staircase should be kept in the center of the building which makes the torsional effects as zero by in coupling the moment it also makes the implication of the irregularity in plan of the building

Ship work like this
in your own course.