基于P－Δ曲线评估桥梁弹性工作状态的方法与应用

摘要

现行实际桥梁结构的静载试验中，无论是采用汽车队列加载，还是堆载法加载，虽可实现分级加载，但难以做到加载点位置不变。另外，对修建于20世纪的部分窄桥，更是难以实现分级加载。基于此，为方便静载试验的进行以及更加精确地了解和判断桥梁结构的实际工作性能，提出基于等效 P －Δ曲线评估桥梁弹性工作状态的方法，解决静载试验中的多点分级加载问题，并结合吉埠大桥静载试验和预制单片 T 梁静载试验2个工程实例介绍其应用，评价桥梁的弹性工作状态与刚度。该方法可供相关工程提供参考，并为以后桥梁检测方法和规范的修编提供依据。%For most static load test on actual bridge structure,whether for vehicle queue loading test or heaped loading test ,it had been multi -point grading load,and it was difficult to ensure the loading point unchange.In addition to some narrow bridges built in last century,the problem is even serious.In order to solve such prob-lems,provide convenience to static load test and judge the actual performance of bridge structure more accurate-ly,this paper presented a method to assess the flexible working status of the bridge based on the equivalent P -Δcurve.Besides,by taking Jibu bridge and prefabricated monolithic T beam as examples,this paper evaluated the flexible working status and its overall stiffness of the above projects.The results obtained can provide a refer-ence to the relevant projects and furnish basis to revise bridge detection method and code at the same time.