Considerations of Vertical Acceleration Induced by Horizontal Earthquake Record for a Building with Underground Stories Based on a SSI 3D Model

Abstract

AbstractThe effects of the vertical earthquake on buildings have typically been less of a concern than the horizontal effects. This is primarily due to the misconception that both the amplitude of the vertical component is smaller than the horizontal component and that the building is stiffer in the vertical direction than in the horizontal direction. The seismic building codes have given less attention to the vertical seismic effect in buildings. In many articles, that have examined the seismic behavior of structures due to horizontal earthquakes without considering soil-structure interaction, the effects of the vertical response of a building to the earthquake are based on the recommendations of codes as a combination of the percentage of dead load and horizontal seismic load or the vertical seismic effect is permitted to be taken as zero for some conditions. Seismic accurate analysis of structures due to the complex dynamic behavior of the soil and SSI, involves consideration of the simultaneous modeling and dynamic analysis of soil and structure. The present study investigated the effects of SSI on the vertical acceleration components of earthquakes by taking time history analysis for three records using ABAQUS software. To achieve this, vertical acceleration induced by horizontal earthquakes record for a 13-storey building with four underground ones, were examined by comparing the results of the time history analysis with or without considering soil. The results show that the effect of SSI on the vertical acceleration component of earthquakes of the building was generally significant.KeywordsVertical component of earthquakesSoil-structure interactionTime history analysis