Performance of a BRB Rc High-Rise Building Under Successive Application of Wind-Earthquake Scenarios

Abstract

High-rise buildings in the regions with multi-hazard (MH) events, such as wind and earthquake, are exposed to more than one type of lateral excitations which act in consecutive manner. Conventionally, in such regions, the maximum of each MH event is used separately to evaluate the performance of buildings while the contribution of preceding event is neglected. When using vibration control devices such as steel dampers, which are effective against both earthquake and wind, accumulation of damage due to continuous input may become a problem. Thus, the current research work aims to investigate the contribution of preceding MH event to the performance of buildings. In this regard, a 20-story RC frame with supplemented buckling-restrained brace (BRB) is designed to satisfy the criteria under the Level-2 earthquake ground motions recommended in Japanese design standard. Then, a total of 16 sets of MH scenarios are created by combining four sets of preceding wind loads with different intensities (17, 20, 25 & 31 m/s of mean speed) and four sets of succeeding earthquake loads of Level-2 intensity. The performance of the RC frame is evaluated in terms of global parameters (such as, natural periods, mode shapes, inter-story drifts, roof displacement profiles, and residual displacements) and BRBs parameters (such as, ductility demands, cumulative plastic deformations, and force-deformation relations). It is observed that the performance of the building with BRB is significantly affected under the successive application of wind-earthquake scenarios in comparison to the application of the single hazard. This result suggests the importance of considering multi-hazard events in the design of buildings.