【作者】 李涛；

【导师】 杨溥；

【作者基本信息】 重庆大学 ， 土木工程， 2011， 硕士

【摘要】 钢-混凝土组合梁是钢材和混凝土材料性能的优化结合,其功能取决于钢梁与混凝土梁之间的组合程度,而钢与混凝土之间的组合程度与接头部位的抗剪连接件的密切相关,PBL剪力键是桥梁钢-混凝土接头部位常用的抗剪连接件之一。目前,对PBL剪力键及钢-混凝土接头的相关研究相对较少,对其受力性能和模拟分析仍需进一步研究。本文以重庆石板坡长江大桥复线桥的钢-混凝土接头为工程背景,应用有限元分析程序对钢-混凝土接头及PBL剪力键在静力和动力荷载下的受力性能进行研究,并对该桥的钢-混凝土接头局部的安全状态进行评估,主要研究内容包括:①采用通用有限元程序ABAQUS建立了钢-混凝土接头中单片PBL剪力连接件的有限元模型,考虑了PBL钢板开孔中混凝土和贯穿钢筋的抗剪销栓作用。通过模拟低周往复荷载和单调加载试验,分析了剪力板和混凝土之间的连接性能和主要影响因素,得到剪力键的荷载-位移骨架曲线,为钢-混凝土接头的动力分析提供了恢复力模型;②根据设计资料分析和钢-混凝土接头试验报告,分析了典型静力荷载工况下钢-混凝土接头局部的受力特征,考察了钢-混凝土接头应力的分布以及剪力板和混凝土的相对位移情况,并与实验结果进行对比分析,验证了本文有限元模型的有效性;③利用SAP2000建立了整桥结构模型,选取了3组三向地震波,对其进行了动力时程分析,得到钢-混凝土接头两端截面的内力时程。采用ABAQUS建立了钢-混凝土接头的局部模型,将SAP计算的最大的一组内力时程作用到钢-混凝土接头上,研究了钢-混凝土接头及连接单元在地震作用下的应力分布和相对位移;④根据对钢-混凝土接头静力和动力有限元分析的结果,确定合理的报警阀值,对该桥的钢-混凝土接头进行局部安全状态评估。更多还原

【Abstract】 Composite beam of steel and concrete box girder is the embodiment of the composite materials of steel and concrete, optimization function of the composite beam depends on the combination between steel and concrete beam, and the combination is closely related with shear connectors in connection part of the joint. PBL shear connector is one of the most frequently used connectors in the part of the joint of bridge. At present, the related research of PBL shear connector and the joint of steel and concrete box girder is also less. More research about the mechanical behaviour and finite element model of the PBL shear connector need to do.Based on the joint of steel and concrete box girder of Chongqing Shibanbo Changjiang Widen Reconstructed Bridge, the stress performance of the joint and the PBL shear connectors under static and dynamic load was studied, appling general finite element analysis software. And the local safety state of the joint of steel and concrete box girder was evaluated.The main work of research as follows:①The finite element model of monolithic PBL shear connector in the joint was established with the general finite element analysis software ABAQUS, simulating the action of self-locking of concrete and rebar throughout in the hole of steel plate. Based on the simulating of monocyclic loading test and cyclic loading test, the connection behaviour between PBL shear connector and concrete and the main influence factors was studyed, and the skeleton-frame curve of the PBL shear connector’s force-displacement curve was gained, which provided the hysteretic curve to the dynamic finite element analysis of the joint;②According to the analysis of designing data and the report of the test, paper analyzes the mechanical behaviour of the joint in conditions of typical static loading, the distribution of the joint stress and the relative displacement between PBL shear connector plate and concrete was studied and compared with the result of the test to proved the rationality of the finite element model;③The whole bridge model was established with SAP2000, and three groups of three directions of the seismics load were chosen, and time history analysis was done to the model to gain the internal force schedules on both ends of the joint. The partial model of the joint was established with ABAQUS, the group of the maximum internal forces time history was applied to the partial model, and the stress distribution and relative displacement of the linkers and the joint of steel and concrete box girder under the action of the seismics load were studyed;④According to the results of static and dynamic finite element analysis of the joint, determine reasonable alarm threshold. The local safety state of the joint of steel and concrete box girder is evaluated according to the general method of bridge health monitoring.更多还原