桥梁用预应力混凝土疲劳安全性能的检测方法研究

Study on Fatigue Performance of Prestressed Concrete Bridge

随着汽车载重量不断加大,桥梁架构及构建承受的动荷载增加,桥梁用预应力混凝土很容易出现疲劳安全问题,针对传统方法在桥梁用预应力混凝土疲劳安全性能检测方面一直存在检测性能低、效率差的问题。提出基于裂缝粘结滑移理论的桥梁用预应力混凝土疲劳安全性能的检测方法。通过分析桥梁用预应力混凝土损伤,引入初始挠度扩大系数法计算荷载挠度,采用网格划分层次法构建预应力混凝土疲劳安全性能的有限元分析模型,在此基础上,引入裂缝粘结滑移理论,计算最大裂缝宽度,对其安全性能进行检测。实验结果证明,采用改进检测方法时,其应力及位移检测均较准确,疲劳损伤检测相比传统方法均要优越,具一定的实用性。

With the increasing load of the vehicle,the construction and the dynamic loading increasedbridge,bridge with prestressed concrete structure is prone to fatigue safety problem,traditional methodsfor safety performance of prestressed concrete bridge in fatigue detection has been a problem of lowefficiency,poor detection performance.A new method for testing the fatigue performance of prestressedconcrete bridge based on the crack bond slip theory is proposed.Through the analysis of damage inprestressed concrete bridges,the introduction of the initial deflection calculation of load deflectionexpansion coefficient method,the finite element analysis model of construction safety performance ofprestressed concrete fatigue using mesh hierarchy,based on the introduction of the bond slip cracktheory,the calculation of the maximum crack width,to test its safety performance.The experimentalresults show that the improved method is more accurate than the traditional methods in the detection ofstress and displacement,and it has a certain practicality.