地震作用下的桥梁碰撞分析改进求解方法

An Improved Algorithm for Seismic Pounding Analysis of Bridges

为了准确研究碰撞效应对桥梁造成的破坏以及对桥梁地震响应造成的影响,针对用于桥梁地震碰撞分析的接触单元模型提了一种改进求解方法。该方法把碰撞模型等效为一个弹簧-振子模型,由振子、弹簧和阻尼器构成。振子的运动过程代表碰撞的压缩和恢复过程。可以通过对运动方程的求解,得到相对压入量、相对压入速度、碰撞力、碰撞持续时间及其相互关系。通过与Hertzdamp模型常用求解方法和Hertz模型计算结果的比较,可以发现改进算法的结果更合理,具有很高的精度。尤其是对于存在大量能量耗散的地震碰撞问题,改进算法比常用算法更具优越性。

To better study the bridge damages and the seismic response caused by pounding,an improved algorithm of contact element model for seismic pounding analysis of bridges was presented.In this algorithm,the impact model is equivalent to a spring-oscillator model which contains an oscillator,a spring and a damper.The oscillator movement represents the compression and restitution phases of impact.By solving the motion equation,penetration displacement,penetration velocity,impact force,impact time and their mutual relationship can be obtained.According to comparing the results of improved algorithm,common solution methods of Hertzdamp model and Hertz model,it is found that the result obtained by improved algorithm is most reasonable and accurate.Improved algorithm has more advantages than common solution methods,especially for solving earthquake-induced pounding problems that there is a mass of energy dissipation during impact.