变速多移动质量耦合作用下多跨变截面箱梁桥振动响应分析  

VIBRATION ANALYSIS OF MULTI-SPAN BOX GIRDER BRIDGES WITH VARIABLE CROSS SECTION UNDER THE ACTION OF MULTI-MOVING MASSES WITH VARIABLE SPEEDS

作　　者：刘鹏[1,2] 荣华[3] 蒲军平[2] 

机构地区：[1]湖南省高速公路管理局,长沙410000 [2]浙江工业大学建筑工程学院,杭州310032 [3]中冶建筑研究总院有限公司,北京100088

出　　处：《工业建筑》2016年第6期85-89,共5页Industrial Construction

摘　　要：针对工程中广泛应用的多跨变截面箱梁桥,考虑移动车辆的惯性力,模拟多个移动质量变速运动耦合振动情况。根据梁桥振动理论,建立多移动质量-简支梁系统的振动方程,分离变量法推导出解耦的强迫振动变系数二阶微分方程。采用附加矩阵方法,对移动质量产生的惯性力用形函数进行离散处理。编制桥梁动力响应计算程序,在时域内数值积分对某高速公路上一座三跨变截面箱梁桥在多辆汽车变速运动作用下的振动响应进行求解分析。计算结果表明:多个移动质量变速运动对梁桥产生的整体振动效应是一种非线性叠加关系;变速移动质量作用下梁桥动位移大于移动力作用下的动位移;连续箱梁桥的动力响应与移动质量的初速度和加速度有关。Coupling vibration of the multi-moving masses on a multi-span box girder bridge with variable cross sections was simulated by considering the inertia force of moving vehicle. Based on the vibration theory of bridge,the vibration model of the multi-moving masses-simply supported beam system was established. A differential equation with variable coefficients was presented according to the separation of variables method. Using additional matrix and shape function,discretization form of the inertia force for moving mass was obtained. Calculation program for solving dynamic response of bridge was worked out. The vibration response of a three span box girder bridge with variable cross sections subjected to vehicle loads with variable speeds was analyzed by numerical integration in time domain.The results showed that the overall vibration effect of multi-moving masses with variable motion on bridges was a nonlinear superposition; and the dynamic displacement of the bridge subjected to the multi-moving masses with variable speeds was greater than that subjected to the moving forces. Furthermore, the dynamic response of continuous box girder bridge was related to the initial velocity and acceleration of moving mass.

关 键 词：公路桥梁 连续箱梁桥 动力响应 多移动质量 变截面 变速 

分 类 号：U441.3[建筑科学—桥梁与隧道工程] U448.213[交通运输工程—道路与铁道工程]