Long period ground motion simulation and its application to the seismic design of high-rise buildings

Abstract

Increasing attention is being paid to the adverse effects of long period ground motion (LPGM) on high-rise buildings. However, it is hard to quantitatively define this special ground motion in seismic design, especially in the cases of regions in which sufficient seismic observations have not been made. To this end, this paper proposes an innovative LPGM simulation method. This method not only involves probabilistic seismic hazard analysis (PSHA), but also overcomes the limitations of the original empirical relation-based method. Firstly, a large number of data taken from typical sedimentary basins are utilized to determine the basin amplification factor model, by which an improved response spectra attenuation formula is developed based on the site amplification mechanisms in different periods. Then, based on the statistical regression analysis of the basin correction factors, the modified group delay time empirical formula is obtained. Furthermore, the conventional PSHA model is refined to determine the scenario earthquake. Finally, the design LPGM is generated by the phase difference spectrum method and its impact on high-rise buildings is embodied via a case study. The satisfactory result proves that the proposed method can effectively simulate LPGM and may have great potential in practice.