预应力混凝土连续箱梁桥破坏性试验研究

以沪宁高速公路新兴塘大桥主桥为例,介绍了预应力混凝土连续箱梁桥破坏性试验的方法,对加载方式、测试方法、试验现象和试验终止条件等进行了详细描述。考虑混凝土和钢筋的非线性行为以及预应力效应,建立了桥梁结构的整体三维非线性实体有限元模型,根据试验实际加载过程对桥梁试验进行了仿真计算。通过对试验测试结果和计算结果的分析,获取了试验桥梁的变形、应力和裂缝的发展规律,研究了桥梁的受力特性、破坏机理和承载能力等情况。研究结果表明,试验桥梁具有良好的刚度和强度,其破坏过程符合传统认识和设计假定,承载能力具有较大的安全储备,能够满足安全与使用要求。试验研究的结论可为预应力混凝土连续箱梁桥的试验、设计与维护提供参考。

Study on Destructive Experiment of Prestressed Concrete Continuous Box Girder Bridge

The Xinxingtang bridge on Huning expressway was taken as an example for introducing the method of destructive experiment of prestressed concrete continuous box girder bridge.The loading and measuring methods and phenomena and stopping conditions of the experiment were presented.The three dimension nonlinear finite element model of the bridge was established considering nonlinear behavior of material and prestressing effect.With this model,the test was simulated.Cracking regularity,mechanical characteristic,damage mechanism and bearing capacity of the bridge were studied through analyzing the results of the experiment and computation.The research shows that(1) the strength and stiffness of the bridge are enough;(2) the damage procedure conforms to the traditional knowledge;and(3) the bearing capacity is more than needed.This experiment provides an important reference for test,design and maintenance of the similar bridges.