预制混凝土梁端预埋槽钢节点静力性能试验

Experimental Study on Static Performance of Embedded Channel Joints of Precast Concrete Beam

摘要:

预制混凝土梁端预埋槽钢节点是一种用于装配式耗能减震结构体系的新型节点。完成了12根两端预埋槽钢的预制混凝土梁静力承载力试验,考虑了槽钢预埋深度、梁端箍筋间距、梁跨中空腔和槽钢偏心等因素对节点承载力的影响。试验得到了槽钢撬出破坏和梁端部混凝土压碎2种破坏模式。试验结果表明,节点承载力随着槽钢预埋深度的增加而增加；梁端部箍筋间距加密能明显提高了节点承载力和变形能力；梁跨中设置空腔对的节点承载力和变形能力影响较小；槽钢偏心对梁产生额外的扭矩,降低了节点的承载力和变形能力。建立了数值分析模型,将数值分析结果和试验结果进行了对比,二者吻合良好,验证了数值模型的有效性,为后继研究打下了基础。

Abstract:

Embedded channel joint of precast concrete beam is a new type of joint system which can be applied to prefabricated energy dissipation and seismic reduction systems. Static bearing tests of 12 specimens were carried out, which considered the influence of the length of the embedded channel steel, the stirrup spacing, the cavity in the midspan of the beam, and the eccentricity of the channel steel. Two kinds of failure modes were obtained: the lever-out of the channel steel and the crushing of the beam-end concrete. The test results revealed the following: the bearing capacity of the joint increased with the increase of the length of the embedded channel steel; stirrup densification could significantly improve the bearing and deformation capacity; the cavity in the midspan of the beam had little influence on the bearing and deformation capacity of the joint; the eccentricity of the channel steel led to the additional torsion, which lowered the capacity of the joint. FEM models were established, and they were verified by comparing the test results and the FEM results, which has built a solid foundation for further research.