多跨变截面连续梁桥在车辆通过时的振动分析  

Vibration Analysis of Multi-span Continuous Beam Bridges with Non-uniform Cross Section Under Moving Vehicles

作　　者：蒲军平[1,2] 汪小超[1] 刘鹏[2] 

机构地区：[1]浙江工业大学浙西分校,浙江衢州324000 [2]浙江工业大学建筑工程学院,浙江杭州310032

出　　处：《中国公路学报》2009年第1期66-71,共6页China Journal of Highway and Transport

摘　　要：针对多跨变截面连续梁桥在车辆通过时的耦合振动问题,采用了移动质量模型下的有限元法进行数值模拟,使用Euler-Bernoulli变截面梁单元模拟桥梁结构,给出了完整系统下的动力求解微分方程组的离散形式,其中移动荷载采用Diracδ函数表示,并采用二节点的三次Hermite插值函数向单元的节点进行分配,对于移动质量模型下所产生的各相关的力采用移动质量单元处理。在假定变截面模式的基础上,推导了梁高呈线性变化及抛物线形变化的矩形截面梁单元刚度矩阵和质量矩阵,编制了有限元动力求解软件,并对变截面多跨连续梁桥在移动质量作用下的动力响应过程进行了数值模拟计算。结果表明:计算结果与一些已发表的简单算例吻合很好。Coupling vibration of a vehicle and a uniform cross sections was simulated. A moving multi-span continuous beam bridge with non- mass model was utilized according to the finite element method. Using Euler-Bernoulli beam elements with non uniform cross section properties, discretization form of an entire system of differential equation for solving dynamic response was presented. Dirac delta function was used to represent the moving load. The node loads were obtained in terms of cubic Hermite polynomials, and a moving mass element was adopted to formulate the pertinent factors relating to the moving mass model. Based on presuming mode of a non uniform rectangular cross section beams with linear and parabolic variable heights in a plane, the stiffness matrix and mass matrix were deduced to analyze non uniform members used in engineering structures increasingly. Finite element method program was worked out and a full dynamic response process of the muhi-span continuous beam bridge with non uniform cross sections subjected to a moving mass was simulated numerically. The results were compared to previously published results for some simple examples.

关 键 词：桥梁工程 多跨连续梁桥 数值模拟 动力响应 移动质量 变截面 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]