Seismic Vulnerability Analysis of Traditional Brick-Wood Buildings with Cracks

Abstract

There are cracks in the wall of traditional Chinese brick-wood buildings, which makes it difficult to evaluate the seismic vulnerability of brick-wood buildings. Zhang Fang's former residence which was a typical traditional brick-wood building in Kaifeng City was selected as the case study. The dynamic characteristics of the structure were analyzed by ambient vibration test to verify the correctness of the finite element model. The stress analysis under static loading and the vulnerability analysis under different seismic waves were carried out for the FEM models with and without cracks to evaluate the failure probability of structure under damage state. The results showed that the dynamic response characteristics of the FEM model with cracks were closer to the results of ambient vibration test than that of the FEM model without cracks. From the static analysis results, the displacement and stress at the junction of the back wall and the gable of the model with cracks increased by over 30% and 25% respectively compared to that of the model without cracks. From the time-history analysis results, the acceleration and displacement of the structure were mainly transmitted and diffused along the longitudinal direction under seismic waves. With the increase of seismic intensity, the structural acceleration amplification factor tends to increase and then decrease, and the inter-story drift angle tends to increase. Compared the vulnerability analysis results of models with cracks to that of models without cracks, the failure probability of FEM model with carcks under different seismic intensity was higher and the reason lied in the weakening of wall stiffness caused by cracks. Finally, wall cracks should be considered in numerical simulations for traditional brick-wood buildings with cracks, thus ensuring more accurate seismic vulnerability analysis results.

Keywords: Traditional brick-wood buildings, Crack effect, Ambient vibration test, Seismic vulnerability analysis