Solving the mystery of China’s thousand-year-old wooden pagoda

The world’s oldest wooden pagoda was built with no nails nearly 1000 years ago in Yingxian, China. During the past ten centuries the 67 m tall building has survived countless earthquakes, thunderstorms and wars. To understand its remarkable structural resilience and durability, a comprehensive analysis has been carried out. This paper describes the particular features of the building, including the extensive use of strong but flexible, multi-layered ‘dougong’ brackets, semi-rigid timber joints and the lack of a structural connection to the foundation. These characteristics are then analysed to determine how they function under extreme loading. A combination of energy-absorbing design, good drainage, sound foundations and woodworm-eating swallows appears to explain its extraordinary longevity.