Simplified Procedure for Rapidly Estimating Inelastic Responses of Numerous High-Rise Buildings with Reinforced Concrete Shear Walls

Abstract

Nonlinear response history analysis (NLRHA) is considered the most accurate procedure for evaluating the seismic performance of high-rise buildings. However, it requires considerable expertise and analysis time, making it inappropriate for some applications involving numerous high-rise buildings (e.g., the seismic loss estimation of a city). To overcome this limitation, a simplified procedure developed based on the uncoupled modal response history analysis (UMRHA) and coupled shear-flexural cantilever beam model (CSFCBM) is proposed. The underlying assumption is that the UMRHA procedure can compute the nonlinear seismic responses mode by mode, where each vibration mode is assumed to behave as a single-degree-of-freedom system. The nonlinear seismic responses are approximately represented by the sum of the modal responses of a few vibration modes. However, UMRHA requires knowledge of the modal properties and modal hysteretic behaviors. Therefore, the CSFCBM was introduced here to estimate the required modal properties and modal hysteretic behaviors. The inelastic seismic demands of the building can be determined using the UMRHA procedure with the computed modal properties obtained by CSFCBM. The accuracy of this proposed procedure was verified considering four high-rise buildings of 19, 30, 34, and 45 stories with reinforced concrete shear walls. The inelastic demands computed by the NLRHA procedure were used as a benchmark and compared with those of the proposed procedure. The results indicate that the proposed procedure provides reasonably accurate demand estimations for all case study buildings. Additionally, the total calculation time for modeling one building, performing dynamic analysis on 24 cases of ground motions, and post-processing the results required by the proposed procedure was about 7 to 45 times lower than that of the NLRHA procedure. Therefore, it can be used for estimating the seismic damage and losses of many high-rise buildings in a city for a specific earthquake scenario or a quick assessment of various seismic design options of a high-rise building in the preliminary design phase.