连续曲线梁桥在多车荷载作用下的动力响应  

Dynamic response of continuous curved bridge under multi-vehicle loading

作　　者：陈水生[1] 罗浩 桂水荣[1] CHEN Shuisheng;LUO Hao;GUI Shuirong(School of Civil Engineer and Architecture,East China Jiaotong University,Nanchang,Jiangxi 330013,China)

机构地区：[1]华东交通大学土木建筑学院

出　　处：《江苏大学学报（自然科学版）》2020年第1期118-124,共7页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51468018);江西省自然科学基金资助项目(20181BAB206043,20181BAB206041)

摘　　要：以某一匝道公路连续曲线箱梁桥为例,分析了该类桥梁的空间车桥耦合振动响应及冲击系数.考虑桥梁阻尼比和桥面平整度的影响,采用通用软件ANSYS模拟桥梁,车辆简化为16自由度模型,采用模态综合法编制了公路曲线车桥耦合振动响应MATLAB程序,研究了多车荷载作用下连续曲线箱梁桥的动力响应.研究表明:主梁竖向挠度冲击系数受横向加载车辆数量的影响较小,跨中截面外腹板动力响应最大,建议采用外腹板处冲击系数进行设计.当纵向车辆间距一定,车速低于22 m·s^-1时,冲击系数在单车工况下最大,且随着纵向加载车辆数量的增多而显著减小;当车速超过22 m·s^-1时,纵向两车和三车工况下,主梁冲击系数有围绕单车工况下冲击系数曲线上下波动的趋势.纵向车辆间距对设计时选取的冲击系数影响较小.Taking a continuously curved box girder bridge on ramp as example,the coupling vibration response and the impact coefficient of space vehicle-bridge of the bridge were analyzed.Considering the influence of bridge damping ratio and bridge deck irregularity,the general software of ANSYS was used to simulate the bridge.The vehicle was simplified to 16-degree-of-freedom model.The coupled vibration response MATLAB program of highway curved box girder bridge was compiled by modal synthesis method,and the dynamic response of continuously curved box girder bridge was investigated under multi-vehicle loading.The results show that the impact coefficient of the vertical deflection of main girder is less affected by the number of transversely loaded vehicles,and the dynamic response of the outer web of the mid-span section is the largest.It is suggested that the impact coefficient at the outer web should be used for the design.When the longitudinal vehicle spacing is fixed with the vehicle speed less than 22 m·s^-1,the impact coefficient is the maximum under the single-vehicle condition and is decreased significantly with the increasing of the number of vehicle loading at the longitudinal direction.When the vehicle speed is more than 22 m·s^-1,the impact coefficient of the main girder under the longitudinal two-vehicle and three-vehicle conditions fluctuates up and down the impact coefficient curve under the single-vehicle condition.The longitudinal vehicle spacing has little influence on the impact coefficient in the design.

关 键 词：连续曲线梁桥 多车荷载 车桥耦合振动 Runge-Kuntta算法 冲击系数 

分 类 号：U443.3[建筑科学—桥梁与隧道工程] TH212[交通运输工程—道路与铁道工程]