为研究梁柱边节点的动态力学性能,采用位移加载控制方式,对3个梁柱边节点组合体试件开展动态加载试验。根据软化拉-压杆模型,预测了节点核心区裂缝的开展,并分析了轴压比和加载速率对节点破坏形态、承载能力、位移延性的影响规律。结果表明:轴压比增大后,节点内裂缝数量减少,节点核心区斜裂缝与竖向轴力的夹角减小;随加载速率的提高,试件断裂面上越来越多的骨料被拉断,节点组合体严重损伤部分发生转移;加载速率提高后,试件的水平抗剪承载力提高9.73%,但试件的水平抗剪承载力随轴压比的变化不明显;节点组合体的变形能力随加载速率或轴压比的提高而减弱。
In order to study the dynamic mechanical properties of exterior beam-column joints,the dynamic loading tests on the specimens combined by three exterior beam-column joints were carried out with displacement control loading. The softened strut-and-tie model predicted the development of cracks in the core area of the loaded joints.The effects of the axial compression ratio and the loading speed on the failure mode,carrying capacity,displacement ductility of the loaded joints were analyzed. The results show that the number of cracks within joints and the angle between diagonal cracks and vertical axial force of the joint core area decrease as the axial compression ratio increases. As the loading speed increases,the number of fractured aggregates grows on the specimen surface,leading to transfer of the seriously damaged part in the combined joints. Also,the horizontal shear carrying capacity of the specimen improves 9. 73% as the loading speed increases,but the effect of the axial compression ratio on the horizontal shear carrying capacity of the specimen is not obvious. The deformation capacity of the joint combination is reduced with the increase of the axial compression ratio or the loading speed.