Improving seismic performance for inclined historical building by using external protection structure: Case study of Yingxian wooden pagoda, China

Abstract

Historical wooden buildings constitute a significant segment of the architectural heritage worldwide. However, these structures are susceptible to component deterioration and structural inclination, potential collapse due to material degradation and the impact of external loads. The fundamental objective in conserving these historical wooden buildings is to safeguard them from such catastrophic failures, thereby preserving their intrinsic value and extending their longevity. To address this issue, a scientific control method based on the principle of minimum intervention has been proposed, termed the “zero-interference method”. This approach is designed to mitigate the progression of structural inclination and enhance the seismic resilience of ancient wooden structures without imposing any disruptive influences. The ancient wooden building is surrounded by an external protection structure (EPS) that is connected to the inclined part. This study uses the FE model of the Yingxian wooden pagoda in China to analyze the structural responses in both pre- and post-reinforcement, validating the effectiveness of the method. Additionally, the parameters of the EPS are discussed. The results reveal that the zero-interference method can effectively mitigate the progression of structural inclination and reduce the seismic responses of the wooden pagoda. The maximum reduction of story drift can reach over 50 %. The wooden pagoda is connected to an EPSwith concentrically braced support by using BRBs, improving the seismic performance. Notably, this study offers a valuable contribution to the field, presenting a methodological framework for augmenting the structural rigidity and curtailing displacement in historical wooden buildings.