插筋灌浆连接水平拼缝受剪性能试验研究与有限元分析

对4个采用插筋灌浆连接的装配式混凝土剪力墙连接试件进行静力加载试验，采用已有的界面受剪承载力计算方法进行计算，并与试验结果进行对比。采用有限元分析软件Msc.Marc对插筋灌浆连接拼缝的受剪性能进行非线性有限元分析，在模型验证的基础上，分析了轴压比、插筋数量以及界面粗糙程度对拼缝受剪性能的影响。研究结果表明：试件的初始破坏为拼缝处混凝土与砂浆的界面破坏，拼缝处出现明显的剪切通缝；混凝土与砂浆界面黏结破坏以后，界面剪力主要由拼缝处的插筋承担，试件呈现良好的延性；达到极限荷载以后，随着试验墙体劈裂裂缝的不断增加以及裂缝处混凝土剥落，试件荷载下降。在实际工程设计中，为了尽量避免拼缝破坏发生在预制构件破坏之前，应按照要求增大拼缝插筋配筋率或选取较高强度等级的插筋。

Experimental study and finite element analysis on shear performance of horizontal grouted rebar connections

In this paper, static tests on the shear performance of 4 specimens of grouted rebar connections used for precast concrete shear wall structure were conducted. Existing methods for calculating the shear resistance of the precast connections were compared with the test results. Then finite element models of the test specimens were established using the commercial finite element packages Msc.Marc. Parametric analyses were conducted to study the effects of axial compression ratio, the number of the interface rebars and the roughness of the interface on the shear performance of the connections. It is shown that the failure initiates at the interface of the mortar and the concrete. The shear resistance of the interface is mainly attributed to the interface rebars after cracking and slipping of the interface. Satisfactory ductility is observed in the test. The failure mode of the specimen at the ultimate state is the splitting of the concrete in front of the inserting rebar. The shear resistance then drops with the spalling of the concrete. It is concluded that sufficient interface rebars be placed at the connection to prevent the failure of the connection before the failure of the precast element in the design practice.