在役钢结构桥梁提升跨的承载状态综合分析与评价

Load-carrying Capacity Assessment of Lift Span in Existing Steel Bridge Structure

为了深入研究在役钢结构桥梁的承载能力,确保桥梁安全运营并及时掌握其工作状态,依托工程实例,采用静载试验、动力特性测试及有限元分析相结合的方法,对在役钢结构桥梁提升跨的承载状态进行综合分析。结果表明:弹性状态下,所测试桥梁提升跨的整体运行状态较差,需进行加固维修;随着服役年限的增加,提升跨的桁架各杆件均存在承载力退化现象,结构刚度不断降低,运行状态逐渐变差;对局部杆件进行加固,能有效改善其承载能力,且整体振动频率略微增加,但在其后服役年限内桥梁整体承载能力的劣化速度加快。

In order to explore the bearing capacity of existing steel bridge in a further step, and keep bridges working well and inspecting their state in time, a comprehensive analysis is made on the load-bearing state of bridge hoisting bridge in service steel structure, relying on engineering examples. The results show that the bearing capacity of elastic state under test bar bearing capacity does not meet the requirements, and improve the whole run across the bridge condition is poor. With the increase of the service life, the load-bearing capacity of the truss is reduced, the stiffness of the structure is decreased and the operation condition is worse. After strengthening the local bar, the bearing capacity of the bar is significantly improved, and the overall vibration frequency is slightly increased, but the deterioration rate of the above indexes is accelerated in the following years of service.