Study On Deformation Mechanism Of Tibetan Dagoba

Tibetan Buddhist temple architecture,an important symbol of multi-ethnic integration,is distributed in vast area of China.Tall,slender and built with brick and mortar,Tibetan Dagoba,which is a representative of Tibetan Buddhist temple architecture,suffers deformation and damage of various degrees due to defected siting(mostly located in earthquake-prone regions)and perennial weathering.In order to provide scientific basis for the protection and utilization of Tibetan Dagobas,it is urgent to research on static and dynamic characteristics and deformation mechanism of Tibetan Dagobas.This paper sets Beihai Park White Dagoba,located in Beijing,as an example.On the basis of combing historical records,the methods used in this paper combines theoretical research,elaborate field surveying,investigation and mapping,long-term monitoring of the Dagoba,on-site environmental random vibration test and finite element method simulation.With these methods,the paper analyzes the deformation and damage mechanism of Tibetan Dagoba under the effect of self-weight,non-uniform subsidence,earthquake(before and after local reinforcement).The main conclusions are as follows:Beihai Park White Dagoba is of similar architectural form comparing to Restored Sa Kya Pandita Ossuary Pagoda in Wuwei,Gansu Province.Due to material difference,Beihai Park White Dagoba possesses lower fundamental frequency,and is prone to vibrate due to external excitation.Beihai Park White Dagoba has sufficient safety stock under the effect of self-weight.According to the existing cracks on the body of the tower,the dominating non-uniform subsidence occurred is unilateral inclined subsidence and basin-shaped subsidence.Before the reinforcement,Beihai Park White Dagoba was damaged at the neck of the tower under medium and large earthquakes of 8 degree.The body of the tower may partially collapse.The reinforcement improves the seismic performance of Beihai Park White Dagoba,while the risk of partial collapse under the action of 8degree large earthquake still exists.Tibetan Dagobas should avoid subsidence occurred on both ends of the structure.Under the action of static force,the structure is subjected to large force at abrupt changes of cross-section,which is the part that requires attention.Under the action of earthquake,the neck of Tibetan Dagoba is the most vulnerable part of the tower body,and the seismic performance of the Tibetan Dagoba can be significantly improved with reinforcement of the tower neck.