Study on the causes of secondary cracks of the eave wall mural of Daxiong Hall at Fengguo Temple in Yixian, Liaoning, China

Abstract

AbstractBuilt in Kaitai 9 years after the beginning of the Liao Dynasty (1020 A.D.), the Daxiong Hall of Fengguo Temple (Yixian County, Liaoning Province) is one of China’s largest existing ancient single-eave wooden architecture structures. In 2012, it was listed on the “Preliminary List of World Cultural Heritage in China.” Preserved Buddhist murals depicting the Yuan Dynasty cover approximately 470 m2 of the hall’s four walls. Since the in-situ reinforcement and protection of the mural, conducted in the 1980s in cooperation with the maintenance and restoration project of the main hall, seriously developed cracks—known as secondary cracks—have become a primary factor affecting the mural’s structural stability. In this study, we conducted a comprehensive investigation using a full-frame digital camera, an industrial endoscope, an infrared thermal imager, an online environmental monitoring system, and a three-dimensional laser scanner. Our results, and other relevant materials, allowed us to deepen our understanding of the existing structural features, the nature of the cracks, the deformation conditions, and the environmental characteristics of the mural. Moreover, we provide a further discussion on the macroscopic formation process of the secondary cracks.