Study on the seismic characteristics of Chinese historic timber buildings

It is imperative to preserve Chinese historic timber buildings (CHTB) because the impacts of time and the environment have seriously reduced the resistance capability of these historical relics. As the most complicated structure, the highest grade and the most typical representation of CHTB, the palace structure was selected as a research object. The unique structural form and characteristics, load-transferring mechanism and seismic characteristics have been studied. It is found that: (1) the raised platform forming the base of the timber column-lintel skeleton possesses very good energy dissipation; (2) the wooden columns are put on the smooth plinths directly without any joint. The sliding vibration isolation between the column footing and plinth is owed to the particular structural fashion. (3) the structural frame become a closed timber structure system with better stability and seismic resistance characteristic according to the two rules in calumniations-ShengQi and CeJiao. (4) the mortise-tenon joints between wooden components show the property of friction damping and energy dissipation. (5) DouGong supports the roof frame and transfers the load from the horizontal member above to the vertical member below. In addition, DouGong exhibits obvious lateral flexibility. There is sliding friction between the tiers of Dou and Gong, which dissipates a lot of energy as a set of vibration reduction springs do. Therefore, Chinese historical timber buildings exhibit good behaviors of energy dissipation and vibration reduction. It may provide information, suggestions and theoretical base for seismic research, protection and maintenance of historic timber buildings.