Conceptual design of a building with columns and shear walls

1.ans

2.ans

Issues in the given Framing plan: Indirect lateral load Transfer in X directions- The beams are connecting to another beams which is ineffective during lateral load transfer. In such conditions, the primary beam is prone to shear failure.

Eccentricity-The longer the distance between center of mass and center of stiffness, the higher torsional moment of the building As per the given plan eccentricity, the building is subjected to higher torsional moment (Torsional flexibility) in both X and Y directions.

Strong beam Weak Column possibility -The size of columns majorly mentioned as 25 cm x 25 cm. But all the beams have much deeper section (50cm). Inertia of beam is visually higher than column. If the column reinforcement is adequately greater than that of beams, we are okay and since we do not have the reinforcement detail, this is doubtful. It is recommended to have slight bigger sizes for column.

3.ans

Answer:

Observations in the given Framing plan:

Floor plan - The floor plan of building is not either uniform or symmetric. So naturally any lateral load induced in the floor will not have 100% influence in same direction. Definitely a Special lateral load resisting system for these torsional moments should be accommodated.

Random Internal columns - Since the internal columns are random, they are unable to transfer

lateral loads efficiently and cannot achieve desirable building response. So, we have to assume and design those columns for only gravity loads.

Floor to floor variations in Partition walls and Beams - Partition walls provide an important mass control in a building and beams play key role in shear transfer from floor to beam. All these elements are not in order. So heavy distortion and distribution of lateral loads will happen.

Suggestion on the Lateral load system & Its foundation:

Heavy torsional forces should be controlled by respective lateral load system. So "Corner Shear walls" are suggested.

The proportion of floor area is greater on the left side than the right side (Irregular quadrilateral). So Corner shear walls on the left side should be heavier than the right.

Corner Shear walls shall preferably be supported over a box foundation. Shear walls should be connected by Link beams to transfer shear from one to the other.

The internal columns shall be supported by isolated footings. Those isolated footings can be connected with Shear walls through Tie beams.