Study On Damage Assessment And Seismic Performance Of Pujiang Arrow Towers In Existing Condition

The emergence of masonry and ancient towers laid the foundation for the development of high-rise buildings in China.It is a classic of the integration of traditional Chinese and non-material cultures,and also a vehicle for the integration of history,culture,science and technology,and art.Sichuan has a unique natural environment and retains many types of ancient pagodas.It has become a precious cultural heritage.Due to the special geographical location,frequent natural disasters seriously threaten the safety of ancient towers.At present,there are many researches on the structure characteristics and reinforcement of ancient towers,but the comparative evaluation of the degree of structural damage in the existing state and the study of seismic performance are still insufficient.Based on this,the main research contents and conclusions of this article are as follows:(1)Based on the analysis of structural damage in the existing state of the arrow tower,the traditional comprehensive index method and the fuzzy mathematics synthesis method were used to compare the damage degree.The analysis results showed that the fuzzy math synthesis method considered the factors more comprehensively,and the assessment results and the field Survey results are closer.(2)Using ABAQUS to establish a three-dimensional solid model,the modal analysis verifies the credibility of the model.The time-history analysis method and response spectrum analysis method were used to study the seismic performance of the arrow towers.The results show that when the response spectrum method is used in the mid-order vibration mode,the plastic deformation occurs first at the window opening at the top of the tower body,mainly due to the shear stress.Excessive shear causes damage at the top window opening;the displacement obtained by the time-history analysis method is large,and the stress in the local area of the bottom normal section exceeds the ultimate strength of the material,and the overall anti-sway stiffness is obviously insufficient.(3)Based on the overall stability in the process of structural reinforcement,a combination of temporary reinforcement and permanent structural reinforcement technology is designed to effectively prevent the construction load from causing the excessive displacement of the pagoda or insufficient bearing capacity during the process of structural reinforcement.A series of unexpected situations will provide a new method for the protection of ancient towers.