冲击荷载作用下引桥悬臂端水平摆动异常原因分析

CAUSE ANALYSIS ON ABNORMAL HORIZONTAL SWING OF CANTILEVER END OF APPROACH BRIDGE UNDER IMPACT LOAD

某高炉平台引桥悬臂端在车辆通行时,梁体本身有明显的水平摆动,影响引桥的安全和正常使用。针对该问题,对该引桥主体结构进行损伤检查、动静载试验,有限元模拟分析等,得出悬臂端主梁摆动的原因为车载作用下桥墩弯曲变形导致的梁体摆动。通过动载试验测得引桥悬臂端水平振动特性,得到不同车速下测点动位移时程曲线,由此计算出不同车速下的冲击系数,并与JTG H11-2004《公路桥涵养护规范》的控制标准进行比较,找出了桥墩弯曲的原因,据此提出针对性的处理建议。

It was found that the cantilever end of the approach bridge of a blast furnace had obvious horizontal swing when the vehicle passed, which affected the safety and normal use of the approach bridge. Aiming at this problem, the main structure of the approach bridge was subjected to damage inspection, dynamic and static load test, finite element simulation analysis, etc., and the reason why the main beam of the cantilever end swung is that the beam body swung caused by the bending deformation of the bridge pier under the action of the vehicle. The horizontal vibration characteristics of the cantilever end of the approach bridge were measured by dynamic load test, and the time-history curves of the dynamic displacement of the measuring point were obtained under different vehicle speeds. The impact coefficients under different vehicle speeds were calculated, and the reasons for the bending of the pier were found out by comparing the limit values of Code for Maintenance of Highway Bridges and Culverts (JTG H11- 2004). According to this, the paper put forward some targeted treatment suggestions.