ZB-200型简支贝雷梁钢便桥静力荷载试验研究

Experimental Study on Static Load of ZB-200-type Simple-supported Bailey Beam Temporary Steel Bridge

G318线竹巴笼大桥因泄洪被冲毁,需在原有桥墩上架设跨度为30 m的上承式ZB-200型战备贝雷梁钢便桥进行抢修,通过桥梁专用软件MIDAS/CIVIL建立桥梁三维空间有限元模型,并采用《装配式公路钢桥多用途使用手册》中错孔挠度理论计算的方法,确定出ZB-200型贝雷梁理论计算的挠度值和应变值,与实桥静力荷载试验测试数据对比,分析不同加载方案下试验数据和理论计算的差异,根据《公路桥梁承载能力检测评定规程》(JTG/T J21-2011)对现有ZB-200型钢便桥的承载能力进行评估和判断。结果表明:ZB-200型贝雷梁钢便桥挠度、应变校验系数、相对残余变位绝对值均满足技术规范的要求,贝雷梁结构刚度达到设计荷载并满足单车50 t运营要求。为今后桥梁抢修工程提供值得借鉴的经验,并提出该桥实行限载、限行的方案,以及加强钢便桥结构的定期检查和检测等相关建议。

Zhubalong Bridge in G318 Line is destroyed because of the flood discharge. The 30m-span deck ZB-200 combat-ready Bailey steel bridge is erected on the original bridge pier for emergency maintenance. The three-dimensional spatial finite element model of the bridge is established through the special software MIDAS/CIVIL for the bridge. The method of theoretical calculation of the deflection of the staggered hole in the Manual for Multi-purpose Prefabricated Highway Steel Bridges are used to determine the theoretically calculated deflection and strain values of the ZB-200 Bailey beam. Through the comparison with the static load test data of the actual bridge, the differences between the experimental data and the theoretical calculation under the different loading schemes are analyzed. The bearing capacity of the existing ZB-200 steel temporary bridge is evaluated and judged according to the document of Rules for Testing and Evaluating Bearing Capacity of Highway Bridges(JTGT J21-2011). The results show that the deflection, strain inspection coefficient, and absolute value of relative residual displacement of ZB-200 type Bailey beam steel temporary bridge all meet the requirements of technical specifications.And the stiffness of Bailey beam structure reaches the design load and meets the requirements of 50 t bicycle operation. The experience worthy of reference for the rush repair engineering of bridges in the future is provided. The scheme of loading limit and traffic limit for this bridge, and the relevant suggestions for strengthening the regular inspection and testing of the steel temporary bridge structure are put forward.