基于荷载试验模拟的箱梁内部应力对承载力影响研究

发布时间：2018-02-16 15:53

本文关键词： 预应力混凝土箱梁主梁应力承载能力荷载试验 ANSYS模型分析　出处：《河北工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着公路交通事业的飞速发展，预应力混凝土箱梁桥在我国的应用也越来越广泛。预应力混凝土箱梁桥有跨径大、正常使用阶段结构体系性能良好等优点，但由于在正常使用阶段桥梁受诸多内因及外因影响，箱梁结构体系也会出现一些病害，影响体系的承载能力。经过专业人员多年多年观测及分析，箱梁桥在恒载、箱梁预应力、温度应力、混凝土收缩徐变、活载应力及箱梁主应力等的作用下发生挠曲变形，从而导致其跨中下挠和开裂。这些因素是否会使箱梁桥的承载力发生变化，如何简单有效的分析预应力混凝土箱梁承载力的理论变化与实际变化参数影响分析是本文研究的主要内容。本文考虑了影响混凝土箱梁桥承载力变化的各项荷载参数，并对这些参数的引用做了说明，推导了这些参数的表达方程，根据对对工程实例做桥梁静载及动载试验得到的试验参数所推导得到的桥梁受力和承载能力与用大型工程软件ANSYS建立梁单元模型得到的理论分析结果加以比较，对箱梁桥的梁单元进行综合截面平衡分析，揭示不同影响因素下箱梁桥承载力变化情况。本文对箱梁桥的静载及动载做了简单的介绍，包括了荷载试验的准备工作、试验方法及实验数据的处理等内容。经过对实际桥梁检测数据的处理，得到桥梁在各种加载状态下各项试验参数，用以对桥梁的承载能力进行评定。同时，运用大型工程软件ANSYS按照桥梁整体参数建立桥梁模型，模拟荷载试验的加载方案得到桥梁的理论试验参数，从而与试验参数进行比较，，研究桥梁在实际正常使用过程中恒载、箱梁预应力、温度应力、混凝土收缩徐变、活载应力及箱梁主应力等对承载力的影响，近年来桥梁结构承载能力评定一直是业内工程师研究的重点，开展并完善这一评定方法也成为可以深入研究的课题，完善桥梁荷载试验并作出桥梁结构性能的正确评定，能够更大程度上推动我国桥梁工程的发展，更精确地挖掘现有桥梁的承载能力潜能。
[Abstract]:With the rapid development of highway transportation, prestressed concrete box girder bridge is more and more widely used in our country. However, due to the influence of many internal and external factors on the bridge during its normal use, there will also be some diseases in the box girder structure system, which will affect the bearing capacity of the system. After many years of observation and analysis by professionals, the box girder bridge is dead and the box girder is prestressing. Under the action of temperature stress, concrete shrinkage and creep, live load stress and main stress of box girder, the flexural deformation occurs, which leads to the deflection and cracking in the middle span of the box girder bridge, and whether these factors will change the bearing capacity of the box girder bridge. How to simply and effectively analyze the influence of theoretical and practical variation parameters on the bearing capacity of prestressed concrete box girder is the main content of this paper. The load parameters affecting the bearing capacity of concrete box girder bridge are considered in this paper. The citation of these parameters is explained, the expression equations of these parameters are deduced, and the test results of bridge static and dynamic load tests for engineering examples are given. Compared with the theoretical analysis results obtained by using the large-scale engineering software ANSYS to establish the beam element model, the comprehensive cross-section balance analysis of the beam element of the box girder bridge is carried out, and the load and bearing capacity of the bridge derived by the parameters are compared with the theoretical analysis results obtained by using the large-scale engineering software ANSYS. This paper briefly introduces the static and dynamic load of box girder bridge, including the preparation of load test. Through the processing of the actual bridge test data, the test parameters of the bridge under various loading conditions are obtained, which can be used to evaluate the bearing capacity of the bridge. The bridge model is established by using the large-scale engineering software ANSYS according to the overall parameters of the bridge. The theoretical test parameters of the bridge are obtained by simulating the loading scheme of the load test, and compared with the experimental parameters, the dead load of the bridge in the actual normal operation process is studied. The influence of box girder prestress, temperature stress, shrinkage and creep of concrete, live load stress and main stress of box girder on the bearing capacity of bridge structure has been the focus of engineering research in recent years. Developing and perfecting this evaluation method has become a subject that can be studied deeply. Perfecting the bridge load test and making the correct evaluation of bridge structure performance can promote the development of bridge engineering in China to a greater extent. More accurately excavate the bearing capacity potential of existing bridges.
【学位授予单位】：河北工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441;U448.213

【参考文献】