Study On The Seismic Performance Of Ancient Tibetan Timber Structure

Tibetan architectures are located in Qinghai Tibet plateau, which lies on a seismically active stretch of the Mediterranean Himalaya seismic zone. Earthquake load is a kind of load form which cannot be ignored. The recently study is mainly focused on the architectural style, decorative arts and religious meaning. At the same time the study on analysis of the structural performance is few. There is no study on seismic performance of Tibetan architectures so far. Therefore, it is necessary to carry out research on the seismic performance of Tibetan ancient architecture.In this paper, a typical timber frame is taken as the research object. Pseudo-static test and numerical simulation are carried out to analyze seismic performance of ancient Tibetan timber frame under earthquake load. The main contents include the following aspects:1. The seismic analysis model of ancient Tibetan timber structure is established based on the on-site investigation from a typical ancient Tibetan structure, and its loadings and constraints are simplified by theoretical analysis.2. According to the analysis model, a refined nonlinear FEM model of timber frame is developed based on ANSYS. Transfer mechanism, deformation and failure modes of timber frame under seismic horizontal force are analyzed. Simulation results show that most of the stress values of timber frame are at a low level under seismic horizontal force and the relative displacements of components above column are negligible.3. Hysteretic behavior is simulated. Hysteretic curve, skeleton curve under cyclic load are obtained. Rule of stiffness degradation and energy dissipation are analyzed. The effect of vertical load to hysteretic behavior and failure modes is studied. In addition, the hysteresis behaviors of semi-rigid joints of timber frame are studied. Results show that the timber frame exhibits stable hysteretic performance and strong energy dissipation capacity; Vertical load is beneficial to seismic performance.4. The pseudo-static test of timber frame is carried out based on seismic analysis model. The occurrence and propagation of cracks of timber frame are observed. Hysteretic curve under lateral cyclic load is obtained. The results of test are compared with numerical simulation.