Vulnerability Analysis Of Reinforced Concrete Tall Piers Based On High Ground Motion Intensity Parameters

Tall pier is a remarkable feature of bridge structure nowadays.Its seismic performance is obviously different from that of middle and low piers.The effect of high order mode on the structural response can not be ignored under the action of earthquake.Seismic vulnerability analysis is an effective method to evaluate structural performance.Under existing technical conditions,the transcendental probability of various damage states of built and built bridges can be given under the existing technical conditions.In order to evaluate the damage degree of tall piers under earthquake action,a numerical model of tall piers is established by the finite element analysis software,and the seismic vulnerability curve of tall piers is established considering the contribution of high modes.The main work is as follows:(1)According to the structure of the site conditions and earthquake epicenter distance from the PEER database to select a group of seismic wave form records,at the same time considering higher modes on the structural response of the contribution,determine the research intensity of ground motion parameters;(2)Determine the structure failure criterion,the quantified description of the seismic performance level of structure,selection of plastic hinge region section curvature ductility ratio as the damage index,analysis software XTRACT of the key sections of Moment Curvature Analysis by calculating the damage index of each section,the damage state of the structure,as demand value;(3)The finite element software is used to establish a reasonable tall pier numerical model,and the incremental dynamic time history analysis is carried out to obtain the structural capacity values under the vibration of various places,and to establish the seismic vulnerability curve of the pier.The study shows that the use of high order ground motion intensity as a ground motion intensity index is more reasonable.In a certain range of high piers,the vulnerability of pier increases with the increase of ground motion intensity,and the vulnerability of structure increases with the increase of pier height.