基于荷载试验的钢筋混凝土简支梁桥承载能力评估

Bearing capacity evaluation of a reinforced concrete beam bridge based on load testing

以某钢筋混凝土简支T梁桥为背景,介绍了钢筋混凝土T梁桥荷载试验的加载程序、测点布置及荷载试验效率系数,测试了桥梁典型截面的应力、变形,在动载试验中测试了该桥的自振频率和不同的行车条件下的结构的冲击系数。运用大型有限元软件对钢筋混凝土桥梁进行数值分析计算,将试验实测数据与理论计算结果进行对比,进而对整座桥梁的实际承载能力作出合理的评估。研究结果表明,该桥挠度校验系数未超出规范限值,结构实际工作性能相对较好;在荷载试验车辆作用下实际的残余变形均满足规范设计要求,结构整体仍处于弹性状态;在动载作用下,实际固有频率均大于理论计算频率,桥梁结构刚度满足要求,即该桥在正常使用极限状态下的安全承载能力及应力状态均满足公路—Ⅰ级荷载的的设计要求。

Based on the background of a simply supported reinforced concrete T beam bridge,introduces the layout of measuring points and load test efficiency coefficient of reinforced concrete T beam bridge load test program,the test load,typical bridge section stress and deformation in the dynamic load test of the bridge self vibration frequency and different driving structure under the condition of impact coefficient. Numerical analysis method of reinforced concrete bridge using finite element software,the experimental data and the calculated results were compared,and the actual bearing capacity of the whole bridge to make a reasonable assessment. The results show that the bridge deflection calibration coefficient does not exceed the standard limits,the structure actual performance is relatively good; in the load test of vehicle under the action of the actual residual deformation can satisfy the design specification requirements,the overall structure is elastic; under the dynamic loads,the actual natural frequency is greater than the calculated frequencies of bridge structure stiffness to meet the requirements of the bridge under the serviceability limit state safety bearing capacity and stress state can meet the highway-Ⅰ load design requirements.