SEISMIC RESPONSES ANALYSIS OF HISTORIC BUILDING BASED ON SOIL-STRUCTURE INTERACTION

The station base is unique and important part of the Chinese historic timber building. Traditionally, when carrying on seismic responds analysis of historic timber building, only upper timber structure was considered based on the rigid foundation hypothesis which neglected the influence of seismic function to station base itself and because of the great rigidity's station base caused strong soil-structure interaction. In this paper, a 3-D finite element model of Xi'an Bell Tower is established to assess the influence of soil-structure interaction on ancient timber buildings. The model consists of timber structure, station base and site soil. The time history analysis method is used to calculate seismic responds of the model based on Viscous-Spring Artificial Boundaries. The results showed that the influence on low-order and the higher order frequencies of the structure are obvious when considering soil-structure interaction. The results also indicate that relative displacement of timber structure second floor amplified 1.23 times and relative displacement of station base-ground enlarged 21.6% when considering soil-structure interaction. Therefore, for timber structure with the great rigidity station base, soil-structure interaction should be consider when carrying on the seismic responses analysis.