Analysis Of The Vulnerability Of Ancient Buildings With Wood Structure Based On Deformation And Energy

In the analysis of seismic performance of ancient timber buildings in the past,we usually take the maximum displacement of the structure as the basic starting point to qualitative considering the seismic capacity of the structure,when the maximum displacement caused by the earthquake,the specification of the maximum displacement does not exceed the limit,can be regarded as structure without damage;But with the development of earthquake technology continues to improve,people gradually realize that when the structure does not reach its maximum displacement when damage may occur,which is the so-called low cycle fatigue damage or plastic accumulative damage;therefore puts forward the double damage index of vulnerability analysis based on deformation and energy.Firstly,the pseudo static test of tenon column frame,brackets,the column was carried out,and the multilayer wood structure vibration test;The energy dissipation capacity of each component can be calculated by pseudo static test,and the damage of the structure can be obtained by shaking table test;The finite element model of shaking table test is established,and correctness of the finite element model is verified by the comparison between the experimental model and the finite element modelAccording to the requirements of the natural vibration period of the finite element model,the site conditions of the building,the seismic fortification intensity,20 seismic waves were selected;With the spectral accelerationS_a as the strength index,the maximum displacement angleθ_max or the overall failure coefficient D as the response index,finite element model was analyzed by IDA（In order to be able to accurately compare with the test phenomenon,but also in order to be able to more easily determinethe structure of the seismic stage,where the intensity index spectral accelerationS_a to its corresponding peak acceleration PGA）;And the discreteness of(PGA,θ_max)and（PGA,D）data points in each interval is determined.On the basis of IDA analysis,the vulnerability curves of the maximum displacement angle and the overall structural failure coefficient are obtained;According to the shaking table test and the results of two vulnerability analysis;In the case of multiple intensity,basic intensity and rare intensity,the structural failure is the same as that of the experiment;In the case of extremely rare intensity,the structural failure is more close to the experimental phenomena with the overall failure coefficient as the response index;On the basis of this,this paper puts forward a new method of seismic evaluation,that is,in the case of multiple intensity,basic intensity and rare intensity,the maximum displacement angle is chosen as the main control parameter for vulnerability analysis;In the extremely rare intensity stage,the overall failure coefficient is chosen as the main control parameter to analyze the vulnerabilityThrough the analysis of the vulnerability of two indicators,the ancient buildings of wood structure meet the requirements of "small earthquake is not bad","moderate earthquake can be repaired" and "great earthquake does not fall".