改进后预制钢-混凝土梁柱节点抗震性能分析

Seismic performance analysis of improved precast steel-concrete beam-column joints

为了研究改进后预制组合梁柱节点的抗震性能,在验证数值模拟准确性的前提下,基于有限元软件ABAQUS建立了11个节点模型,分析各参数变化对节点抗震性能的影响规律.结果表明,各试件在低周往复荷载作用下的滞回曲线都比较饱满,等效黏滞阻尼系数在0.266~0.362范围之内,新型预制节点具有良好的耗能性能;新型预制节点的承载力和延性系数分别比传统形式预制节点高5.4%和12.8%,并且其刚度退化能力以及能量耗散能力也优于传统形式预制组合节点;钢梁和钢接头强度的增加可以提高试件在荷载作用下的变形能力,但是对于提升试件承载力、刚度退化和强度退化能力的影响很小;钢接头埋置长度和预制梁内纵筋强度的增加能延缓试件的刚度退化和强度退化的速度,提升试件的承载能力和耗能能力.综合考虑,钢接头埋置长度至少应为200 mm,同时预制梁内纵筋强度等级应高于HRB335,以保证节点有良好的变形性能.

In order to study the seismic performance of the improved prefabricated beam-column joints,11 node models were established based on the finite element software ABAQUS to analyze the influence of various parameters on the seismic performance of the joints.The results show that the hysteretic curves of all specimens are full and the equivalent viscous damping coefficients are in the range of 0.266~0.362.The new prefabricated joints have good energy dissipation performance.The bearing capacity and ductility coefficients of the new prefabricated joints are 5.4%and 12.8%higher than those of the traditional prefabricated joints,and the stiffness degradation ability and energy dissipation ability are also better than those of the traditional prefabricated joints.The increase of the strength of steel beam and steel joint can improve the deformation ability of the specimen under load,but it has little effect on the bearing capacity,stiffness degradation and strength degradation ability of the specimen.The increase of the buried length of the steel joint and the strength of the internal longitudinal bars of the prefabricated beam can delay the stiffness degradation and the speed of strength degradation of the test piece,and improve the bearing capacity and energy dissipation capacity of the test piece.Taking comprehensive consideration,the buried length of the steel joint should be at least 200mm,and the strength grade of the internal longitudinal bars of the prefabricated beam should be higher than HRB335 to ensure good deformation performance of the joint.