An Investigation on the Traditional Timber Structures Reaching Heights up to 113m: Based on Fieldwork and Structural Mechanics Analysis of 'Tianche' in Sichuan

This study examines Tianche, an ancient towering timber structure used in well salt production in Sichuan, China. Originating in the Han Dynasty and maturing in the late Qing Dynasty, the Tianches can reach up to 113.32 m and represents a unique craftsmanship and structural system that is rare worldwide, yet remains largely unexplored in scholarly research. This paper systematically delineates the craftsmanship and structural principles of Tianche using a combination method of anthropological fieldwork and structural mechanics analysis. It focuses on unraveling how small-sized logs were utilized to construct these towering structures under pre-industrial conditions. The paper unveils, for the first time, the key features of the Tianche's structural system, including its self-locking mechanisms, frictional force transmission, and hollow columns. These innovations not only reinforce the structural strength and stability but also demonstrate the feasibility of building over hundred-meter-high structures using small-sized logs. This research addresses a significant gap in the study of timber structures featuring hollow, bundle-like columns with frictional force transmission, presenting new possibilities beyond mainstream structural systems. Furthermore, it discussed the distinct environmental context and cultural significance of Tianche, providing invaluable insights for future heritage conservation research and projects.