装配式混凝土梁柱节点抗震性能试验与数值模拟

为研究不同螺栓强度等级对新型装配式半刚性混凝土梁柱节点抗震性能的影响,分别对螺栓等级为5.6级和8.8级的梁柱节点进行了足尺试验,分析了节点的滞回曲线、骨架曲线、割线刚度、等效黏滞阻尼系数等抗震性能指标,并基于ABAQUS有限元软件对现浇节点和5.6级螺栓连接的试验节点进行了数值模拟。结果表明:基于5.6级和8.8级螺栓连接的半刚性梁柱节点均具有良好的抗震性能和耗能能力,2组梁柱节点构件的刚度均随着位移等级的增加而逐渐降低,与5.6级螺栓连接的节点相比,8.8级螺栓连接的节点刚度退化速率较快,且正向加载下5.6级螺栓连接节点的极限承载力为8.8级螺栓连接节点的85.42%,负向加载下5.6级螺栓连接节点的极限承载力为8.8级螺栓连接节点的83.68%; 有限元模拟结果具有较高的准确性,能够很好地反映节点构件的抗震性能; 与现浇节点对比发现,现浇节点在耗能能力方面比试验节点好,但试验节点的极限承载力要优于现浇节点; 所得结论可为装配式半刚性梁柱结构的抗震设计提供依据,为新型装配式梁柱节点构件的发展及应用提供参考。

Experiment and Numerical Simulation on Seismic Performance of New Type of Prefabricated Concrete Beam-column Joint

In order to study the impact of different bolt strength grades on the seismic performance of the new type of prefabricated concrete beam-column joint, full-scale tests were carried out on the beam-column joints with 5.6 and 8.8 grade bolts, respectively. The seismic performance indicators such as the hysteretic curve, skeleton curve, secant stiffness, and equivalent viscous damping coefficient of the node were discussed. Moreover, based on ABAQUS finite element software, the cast-in-place joint and the test joint with 5.6 grade bolt connection were numerically simulated. The results show that the semi-rigid beam-column joints based on 5.6 and 8.8 grade bolt connections have good seismic performance and energy dissipation capacity. The stiffness of the two groups of beam-column joint members gradually decreases with the increase of the displacement level. Compared with the joint connected by 5.6 grade bolts, the stiffness of the joint connected by 8.8 grade bolts degrades faster, and under the positive load, the ultimate bearing capacity of the joint connected by 5.6 grade bolts is 85.42% of that of the joint connected by 8.8 grade bolts. Under negative loading, the ultimate bearing capacity of the joint connected by 5.6 grade bolts is 83.68% of that of the joint connected by 8.8 grade bolts. The finite element simulation results have high accuracy and can well reflect the seismic performance of joint members. The cast-in-situ joints are better than the experimental joints in terms of energy consumption, but the ultimate bearing capacity of the experimental joints is better than that of the cast-in-place node. The research results can provide a basis for the seismic design of prefabricated semi-rigid beam-column structures and provide a reference for the development and application of new prefabricated beam-column joint members.