Conceptual design of a building with columns and shear walls

Challenge 5

Question 1:

• 

1. All the corners of the column given above have same and equal value, and the floor is enclosed within the RC wall system, thus the system possess good shrinkage control
2. This cannot be considered as asymmetrical plan, thus it lacks tensile capacity and force configuration
3. This has less stiffness
4. This will be less prone to Torsion
5. The quantity of reinforcement required will be less.
6. But this is architecturally very beautiful

• 

1. The walls of the system are arranged in two orthogonal horizontal direction, with two way symmetry, which makes them possess better stiffness
2. Here, the corners are more prone to shrinkage
3. These are less prone to torsion, as the centre of mass and stiffness coincide
4. Mat or Raft foundation is best suitable for this system

• 

1. This system of wall is also not considered as asymmetric, the wall are not arranged in two orthogonal horizontal direction,
2. Here, the floor will have more shrinkage.
3. This system is more prone to torsion during earthquake
4. This wall system possess worst redundancy, because of the load distribution concentration at one side.

Question 2:

• In the given plan, the beams are stronger than the columns, therefore chances of column failure is more , If the beam does not continue straight in full span, but the axis is offset to the column between them, then there won't be any smooth slow of internal forces through thr longitudinal bars across the columns in the span
• Beams with long span have their top reinforcement at the supports governed by factored gravity loads, which results in beam overstrength
• This can also create the possibility of plastic hinge occuring away from the face of the column, caused due to the carried overstrength of beam to the capacity design shears of beams and columns.
• From the observations we can see that there is variation in the perimeter of the plan and there is a discontinuity
• B3 and B4 are not in the same offset, Even when the beam axis is not offset from the span to span, the smooth flow os internal forces from the beams to the column is impaired by a large eccentricity between the axis of the bea, and the supporting column.
• Therefore, as an alternative to this we can

1. Reduce colum forces and add bracings. That means, the short beam span should be neglected, and 5 to 7m should be preferred over longer ones.
2. To reassemble the grid pattern of the floor,

Question 3:

• The overall layout of the frame is a structural frame is very important while considering the impact of the structure on seismic effect
• The partition walls and the interior beams supporting the slabs should have a different layout in different storeys,
• The building should sonsist of the shear wall or braced frame and moment resisting frame to resist the total design force in proportion to the lateral stiffness
• The beam depth, geometric details of the individual plane frames, location in the plan, structure's architectural value, cost effectiveness considering the earthquake resistance, flexibility, reinforcement detailing, workmanship of high rise building, supervison on site, the lateral loads etc should be taken in account
• The frames and walls should be cost effectively combined in a single lateral load resisting system.
• Along with these, Raft or mat foundation is idealy perfered to avoid horizontal displacement.