Seismic Performance Analysis Of Yingxian Wooden Pagoda Based On Stiffness Eccentric Model

Yingxian Wooden Pagoda is the tallest existing multi-storey wooden pagoda-style pagoda in the world,with extremely high scientific and cultural value.Some achievements have been made in the study of the static and dynamic performance of the Yingxian wooden Pagoda,but there are few achievements in the modification of the numerical model,the study of the coupling law of the flat-torsional coupling caused by the eccentricity of stiffness,and the analysis of the uncertain seismic response.Aiming at the above shortcomings,and constructs the research idea of this paper.The research work can make up for some blanks in the static and dynamic analysis of the wooden Pagoda in Yingxian County,introduce the concept of stiffness eccentricity,and analyze the seismic response of the wooden Pagoda,which can provide a reference for the seismic performance evaluation of the wooden pagoda in Yingxian County.The main contents include:(1)The eccentricity of stiffness makes the inertial force and the resistance force do not coincide,resulting in the vibration of the structure in translational and torsional coupling.The concept of stiffness eccentricity is introduced into ancient buildings,and the equations of motion of single-story and high-rise bidirectional eccentric structures are first deduced and verified,and then the effects of eccentricity angle,eccentricity distance,uniform eccentricity and non-uniform eccentricity on the seismic response of the structure are discussed.This research is the theoretical foundation for the earthquake response research of Yingxian Wooden Pagoda.(2)Refer to the literature,conduct on-site environmental excitation tests for the corresponding county wooden towers,obtain acceleration signals,and preprocess the vibration signals of each floor;use the spectral analysis method to determine the frequency,and use the random subspace method to identify and obtain Multi-order translational and torsional modal parameters,including frequency,damping ratio and mode shape;combined with the previous eccentric dynamic model,a dynamic model of Yingxian Wooden Pagoda considering stiffness eccentricity was established.Based on the field measurement results,the feasibility of the model was verified again.(3)Combined with the dynamic equation of the Yingxian wooden tower above,the seismic response analysis of the Yingxian wooden tower considering the stiffness eccentricity is carried out,and the displacement and acceleration are used as indicators to study the horizontal-torsional coupling vibration law of the wooden tower.The difference in the response of the wooden tower when eccentric,and then using the interstory displacement angle as an index,the seismic response was evaluated.(4)The ground motion has significant randomness.Based on the deterministic seismic analysis results,the random ground motion model and the concept of PDEM are introduced,and the seismic performance of the Yingxian Wooden Pagoda is analyzed by the method of reliability.Firstly,a stochastic ground motion model under the action of frequent earthquakes is established,with displacement and acceleration responses as indicators,and then a random earthquake response analysis based on probability density evolution is carried out corresponding to the county wooden pagoda using this model.The seismic reliability of the wooden pagoda is calculated.88 figures,30 tables,and 77 references...