Influence of Shear Wall Location on the Lateral Performance of Reinforced Concrete Buildings

The location of shear walls has a great effect on the lateral behavior of RC building frames under wind and earthquake loads. Shear walls are the main vertical structural elements that resist lateral loads and limit the drifts of multi-story buildings. This article examines how the change in locations of shear wall along the building length affects the stiffness, inter floor drift, torsion and global seismic response of an RC building. A number of arrangements are studied, such as central core, perimeter, corner and asymmetrical. Central core shear walls, which are typically located around elevator shafts along with the stairs, offer moderate to high stiffness and reasonable torsion control ideal for buildings with a regular mass pattern. The lateral rigidity of multistory frame structure is significantly increased by perimeter shear walls, which also reduce inter- story drift especially in tall building, but should be evenly distributed to prevent torsional irregularities. When they are arranged symmetrically, corner shear walls gives maximum torsional resistance and global stability. Conversely, asymmetric or irregular arrangement of the shear walls can cause torsion, non-uniform drift and have the potential to soft-story mechanisms (mechanisms that makes the structure more vulnerable to ground shaking), making the structure more vulnerable to earthquake. The finite element results show shear wall configuration has critical impact on natural periods, base shear distribution, and story forces. The study illustrates that there exists an optimum combination of symmetry and appropriate spacing between walls for efficient resolution of lateral loads. Results show that perimeter and corner configurations are overall more efficient for tall buildings whereas central cores offer a better compromise between architectural functionality and structural performance.