武汉青山长江公路大桥引桥荷载放大系数研究  

Study of Live Load Amplification Factor for Approach Bridge of Qingshan Changjiang River Highway Bridge in Wuhan

作　　者：刘浪[1,2] 王杰[1,2] 叶仲韬[3] LIU Lang;WANG Jie;YE Zhong-tao(State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing 400074, China;School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China;China Railway Bridge Science Research Institute, Ltd. , Wuhan 430034, China)

机构地区：[1]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074 [2]重庆交通大学土木工程学院,重庆400074 [3]中铁大桥科学研究院有限公司,湖北武汉430034

出　　处：《世界桥梁》2021年第5期66-71,共6页World Bridges

基　　金：国家自然科学基金项目(51708069);重庆市基础研究与前沿探索项目(cstc2018jcyjA2535)。

摘　　要：针对桥梁实际运行荷载效应与规范设计荷载效应差异较大问题,以武汉青山长江公路大桥引桥为工程背景,基于周边具有相似交通情况的既有跨江桥梁实测动态称重(WIM)数据和预测统计车辆特征,采用蒙特卡洛法构造自然车列对引桥4种典型连续梁桥有限元模型进行影响线加载,分析95%保证率分位值时正常行驶与自然堵车状态下各控制断面处的荷载放大系数。结果表明:对于4种典型连续梁桥,正常行驶状态下荷载放大系数β<1,自然堵车状态下部分控制断面荷载放大系数β>1;最大荷载放大系数对应内力类型为连续梁墩顶负弯矩,是实际自然车列作用下的控制内力;桥墩墩顶负弯矩等控制内力的荷载效应计算时,荷载放大系数β为1.2~1.5。In the service stage,the load effect in a bridge is not always consistent with the design load effect.In this paper,the Qingshan Changjiang River Highway Bridge in Wuhan is used as a case for the study.The weigh-in-motion(WIM)data and the predicted vehicle parameters on the surrounding existing river-crossing bridges with similar traffic conditions were introduced into the finite element models of approach bridges of four typical continuous girder bridges,the influence line of vehicle loads figured out by the Monte Carlo method was found,and the live load amplification factors of each control cross-section in the normal riding condition and during traffic congestion when the guarantee rate was set at 95%were analyzed.As per the analysis,for the four typical types of continuous girder bridges,the live load amplification factorβis less than 1 in the normal riding condition,while the live load amplification factorβof the local control cross-section during traffic congestion is above 1.The internal force related to the maximum live load amplification factor is the pier-top negative bending moment in the continuous girder,which is the control internal force under the actual natural vehicle loads.When calculating the load amplification effect of the control internal force,such as pier-top hogging moment,the live load amplification factorβshould be between 1.2 and 1.5.

关 键 词：连续梁桥 汽车荷载 WIM数据 车辆特征参数 荷载效应 荷载放大系数 桥梁设计 

分 类 号：U448.215[建筑科学—桥梁与隧道工程] U441.2[交通运输工程—道路与铁道工程]