Plan Geometric Effect on High-Rise Buildings Under Earthquake Shaking

High-rise buildings have become an integral part of modern cityscapes with their iconic designs and efficient use of space. With increasing architectural needs, such buildings usually have poor plan geometry and may cause an unexpected drift pattern or force distribution among structural elements; sometimes this leads to damage or collapse of entire buildings due to their unusual modes of oscillation. Moreover, building codes for high-rise buildings (e.g., IS 16700) mostly ignore such irregular plan geometries. Hence, an attempt is made to understand the plan geometric effect on the inelastic behaviour of high-rise buildings with different plan geometries. 20-storey buildings with different shapes (e.g., Rectangle and H) are considered. These buildings are designed and detailed as per building code provisions. Inelastic behaviour is obtained using nonlinear static analysis using SAP2000 software. Response parameters considered include modal participation ratio, natural period, base shear, maximum interstorey drift, and damage mechanism. Behaviour of these buildings is compared based on the level of damage to structural elements. The damages in high-rise buildings shall be reduced by providing structural walls.