轨道交通双U形-箱形连续梁桥结构整体力学性能试验研究  

Experimental Study on Overall Mechanical Property of Double U-shaped and Box-shaped Continuous Girder Bridge Structure for Rail Traffic

作　　者：黄继成[1] 

机构地区：[1]上海申通地铁集团有限公司,上海市226001

出　　处：《城市道桥与防洪》2018年第11期141-143,147,共4页Urban Roads Bridges & Flood Control

摘　　要：以上海轨道交通17号线工程为工程背景,通过实桥荷载试验及理论分析研究了节段拼装双U形-箱形截面连续梁桥结构的整体力学行为。试验选取了3座主跨70 m、1座主跨55 m以及1座主跨50 m的双U形-箱形连续梁桥为研究对象,每座桥4个加载控制部位,采用2列6节满载车编组的轨道交通车辆进行静力和动力加载测试。研究表明:在相当于设计荷载水平的试验荷载下,各桥梁结构处于弹性工作状态,其变形增量、应力增量均随荷载近似呈线性规律变化;列车以不同速度、不同车辆数正常行驶时,实测主梁动力系数小于1.15;实测主梁中跨跨中最大横、竖向振幅分别为0.47 mm、0.42 mm,横、竖向加速度最大幅值分别为0.92 m/s2、0.77 m/s2;大桥实测各阶振动频率比理论计算值大,实测一阶横向自振频率介于2.700~5.770 Hz,前3阶振型的阻尼比介于1.64%~3.47%。Based on the engineering background of Shanghai Metro Line 17, the article studies the overall mechanical properties of the segment assembly double U-shaped and box-shaped cross-section continuous girder bridge structure through the load test and theoretical analysis of the bridges. Taking three 70-m main span, one 55 m main span and one 50 m main span double U-shaped and box-shaped continuous girder bridges as the study objects, each bridge has four loading control points, two six-car full loading marshaling rail traffic trains are used to carry out the static and dynamic loading tests. The study shows that each bridge structure is at the elastic operating state under the test load amount to the design load level, the change of its deformation increment and stress increment is approximately linear with the load. The measured dynamic coefficient of the main girder is less than 1.15 during the normal operation of the train with the different speeds and the different cars. The maximum horizontal and vertical amplitudes in the measured middle span of the main girder are separately 0.47 mm and 0.42 mm, and the maximum amplitude values of horizontal and vertical accelerated speeds are separately 0.92 m/s2 and 0.77 m/s2. The measured vibrational frequency of each order of bridge is larger than the theoretical calculation value. The measured first-order horizontal natural vibration frequency is between 2.700 Hz and 5.770 Hz. The damping ratio of the first three-order vibration mode is between 1.64% and 3.47%.

关 键 词：连续梁桥 节段拼装 双U形-箱形 静力行为 动力行为 

分 类 号：U446[建筑科学—桥梁与隧道工程]