高桥墩塑性铰抗震性能分析

A Plastic Hinge Analysis of the Seismic Performance of the High Bridge Pier

为分析高桥墩在地震作用下形成的第二塑性铰对桥墩抗震性能的影响,以内昆铁路花土坡特大桥为实例,通过ANSYS软件建立弹塑性有限元仿真模型,并通过ANSYS软件的屈曲分析功能确定桥墩屈曲荷载,赋予模型铰的初始偏移,再将屈曲荷载加载到模型上.通过软件分析功能,计算非线性模型在该荷载作用下从桥墩钢筋屈服到混凝土被压碎至截面不断绕中和轴转动并形成塑性铰的各部位应变,确定塑性铰的其形成位置.最后,通过分析计算得出的数据,分析第二塑性铰对于桥墩在极限荷载下的抗震性能的影响.

For the analysis of the effect of the second plastic hinge which is formed by the impact of the earthquake, on the pier seismic performance of the high bridge pier, the paper, taking the slope within the Kunming Railway Bridge take as an example, firstly, established the elastic-plastic finite element ANSYS software simulation model. Secondly, it determined the buckling load piers by using the buckling analysis function of ANSYS software, gave the model an initial offset, and then loaded the buckling load into the model. Thirdly, it calculated the non-linear model in the loads using the analysis software, from when bridge piers reinforced concrete was crushed to yield to the cross-section continuously rotating around the neutral axis, to eventually the formation of plastic hinges in all parts of the strain, and determine the loca- tion of the formation of plastic hinges. Finally, by analyzing the calculated data, the paper analysed the effect of the second plastic hinge on the seismic performance of the bridge piers under the ultimate load.