Conceptual design of a building with columns and shear walls

1) In the given sturctural diagram the shear walls arein the L shaped structure at the edge of the plan. so the sturcture with that given plan as the structure is more restrained it will be more shrinking, expanding and cracking. .

In the second diagram given that the shear walls are on the middle of the structure and they are in the rectangular shape that it represents that the shear walls in the structure also decide whether the floor vibration is more or less in the structure it will be better placing a column at the corners.So that it will reduce the cracks instead of having a shear walls at the corner in the structure.

In the third diagram the shear walls are in the one at the middle which the shape of the shae wall is rectangular but the lenth is more compare to the other but in the opposite direction two shear walls are given the perpendicular direction so that by oberving the three diagrams

We can see in the first and second diagram that all the four shear walls are symmetrical and are uniform in size so there will be uniform distribution of seismic forces.but in the 3rd diagram walls are dissimliar and unsymmetric, so the walls which are more strong will yield first

The torsional stiffness of the 1st diagram will be more compared 2nd beacuse it is directly proportional to the stresses and torsional stiffness of 2nd diagram will be lesser, and it will be higher in case of third diagram.

Redundancy will be higher in 1st and 2nd when compared to option 3rd Because the left side of the structural system of the wall will not carry the load equally in either direction in 3rd due to unsymentical in size.

In the first figure the L shape walls are given so these walls have high stiffness and strength in both horizontal directions and subjected to biaxial bending and bi-directional sheaars during the earthquake.

When most of the walls are placed around the staircase and lift core area it produces large eccentricities in plan or creates a torsionally sensitive building.

shear walls will carry the earthquake load to the foundation and structure has greater strength and stiffness in the direction of their orientation.

shrinkage in the longitudinal direction can be ignored. However, that may not be the case for perpendicular to grain shrinkage. Accumulated effects in the boundary chords of shear walls can degrade the performance of the shear wall system and may need to be addressed with shrinkage compensating devices.

In the first figure there is no architectural disturbance as the walls are L shapedand in the other two figures they are on the front face so to some extent they contribute to the architectural constraints of those plans.

2) In the given plan, the frames are not continous and symmetric and one of the column is not unifrom.
and because of irregularity of frames ,from earthquake point of view it not safe due to lack of redundancy and it will suffer from load multiplicity, fewer plastic hinges and less cost effective use of concrete. If there is termination at the beam column joint ,then there will be no uniform transfer of internal stresses. and in this layout ,only the top frame beam is continous,and in the bottom two frames there is column at the joint,i.e there is termination at one end,and then after termination a new beam is laid. these kind of arrangements make a lot of problems on the site, hence they should not be preferred and we can see in the beam B7 only one end is supported by column, where as the other is left to be supported by beam, this kind of arrangement is not permissible because it may lead to soft storey. in this plan column 8 and beam 6 centres should coincide with each other, if they do not coincide it will lead to torsion. and the maximum permossible eccentricity is given by b/4, and it should not be more than that according to code provisions. there is chance of torsional flexibility in the building as we can see that there is a room in the plan which is extending outside the plan , and if the lateral force acts on this area there will be rotation insome parts of the building. fundamental translational mode of vibration is larger than fundamental rotational mode of vibration because translational mode is due to the irregularity or discontinuity of frames from earthquake point of view it not safe due to lack of redundancy and it will suffer from load multiplicity, fewer plastic hinges and less cost effective use of concrete. since there are two frames which are irregular where as if we see the rotation or torsion is only due to the torsional flexibility in the building as we can see that there is a room in the plan
which is extending outside the plan , and if the lateral force acts on this area there will be rotation insome parts of the building. as there is only one source of damage due to rotation and two for translational in the form of frames, hence translational mode of vibration will be higher.

3) The above plan that is given is totally unsuitable for normal areas and also in Earthquake prone area.
In seismic region the lateral and vertical loads play important criteria because it helps in resisting the failure against the earthquake as the loads. Resultant will not co inside with the center of the mass of the structure it becomes eccentric and not suitable for any type of areas. In this plan a flat slab is more appropriate than a regular beam column junction as it provides support to the columns without any provision of the beam which
reduces the weight of the building and also helps in the ductility which indirectly helps to maintain the structure in the the earthquake prone areas. Apart from flab slab a wooden structure is also appropriate which reduces the weight of the building and also helps to maintain the structure in the the
earthquake prone areas.