Experimental Study Of Seismic Behavior Of Zhutou-puzuo Of The Yingxian Wooden Pagoda

The Yingxian Wooden Pagoda is an existing antient wooden building in typical Liao-Song dynasty style with the longest history and the highest height in China.It has very important value in history,cultural,art,science and emotion.Due to the long-term construction,coupled with long-term natural erosion and man-made damage,the wooden tower has suffered serious damage and is still in a state of urgent repair.However,because of complex internal structure and unclear understanding of the force transmission path,it’s necessary to study the important nodes of the wooden pagoda before protecting itself.There are 54 kinds and 448 types of Puzuo joints in the whole tower,which are important components of the pagoda.Carrying out researches on the seismic performance of Puzuo joints,considering the influence of different factors on their seismic performance,plays vital roles in protection of the Yingxian wooden pagoda.(1)The BIM models of all Zhutou Puzuo joints of outer circle on the first to fifth floors of the Yingxian Wooden Pagoda were established.It was sorted out that the structural difference of Zhutou Puzuo joints were quantities of Pu and containing Ang element or not.Considering the effects of three factors,including structural difference and vertical loads,on the seismic performance of Zhutou Puzuo joints,the Zhutou Puzuo joints from 2nd to 5th floors open-floor outer circle were adopted as prototype joints,and corresponding scaled test models were manufactured.The plans of measuring and loading were established.These above made a foundation on exploring the influence of the above two factors on the seismic performance of Zhutou Puzuo.(2)It was finished to research on the effects of structural difference on seismic performance of Zhutou Puzuo.Zhutou Puzuo’s capacity of energy dissipation and horizontal bearing developed with increasing number of quantities of Pu,and Zhutou Puzuo with Ang element had stronger capacity of energy dissipation and horizontal bearing than the one without Ang element.In addition,increasing number of quantities of Pu reduced the proportion of elements slip deformation,and Ang element made difference with position where components occured the largest percentage of slip.Furthermore,the analyzing of transmission path of vertical load indicated that components in the plane of Nidaogong beared more vertical loads in Zhutou Puzuo with Ang element than the one without Ang element.And some parts of vertical loads were divided into horizontal component force because of the angle between Ang element and below elements and were undertaken by friction between elements.(3)It was finished to research on the influence of different vertical loads on seismic performance of Zhutou Puzuo.The 8 test models were divided into 4 groups by location of floor and carried out horizontal low-cycle load test under two unsimilar vertical loads.By comparing the test results,the commonalities and characteristics of the four groups of test results were obtained.When vertical loads become heavier,both of the capacity of energy dissipation and horizontal bearing were enhanced and the proportion of elements slip deformation was reduced but the components occured the largest percentage of slip remained the same.Raising the vertical loads moved down the failure position of the components in Zhutou Puzuo joints in the meanwhile it boosted the damage degree of the components.