方钢管混凝土柱-不等高钢梁框架节点地震损伤演化过程分析

为研究方钢管混凝土柱-不等高钢梁框架节点在地震作用下的损伤演化过程,基于4个方钢管混凝土柱-不等高钢梁框架节点的抗震性能试验,运用有限元分析软件ABAQUS对梁柱节点进行了数值分析,并选取了适用于此类异型节点的双参数地震损伤模型.通过有限元结果和损伤模型分析了不等高钢梁框架节点在低周反复荷载作用下的损伤发展过程.结果表明:所选取的损伤模型能更好地反映节点从"基本完好"到"完全破坏"的损伤演化规律,且能够定量确定节点不同破坏程度的损伤限值;节点的地震损伤主要集中在高梁上下翼缘螺栓连接处,并随着加载循环次数的增加,损伤累积不断加大,最终破坏模式为高梁端塑性铰破坏.研究结论为该类节点基于损伤的抗震设计方法以及地震损伤评估提供了理论依据.

Seismic damage evolution process analysis on frame joints with concrete-filled square steel tubular column-unequal depth steel beam

In order to analyze the damage evolution process of frame joints with concrete-filled square steel tubular column-unequal depth steel beam under earthquake,numerical analysis were carried out of joints by using the finite element analysis software ABAQUS based on the seismic performance tests of 4 frame joints with concrete-filled square steel tubular column-unequal depth steel beam,and a two-parameter seismic damage model suitable for such heterotypic joint was selected.Damage development process of frame joints with unequal depth steel beam under low cycle reversed loading was analyzed by finite element results and damage model.It is founded that the selected damage model can better reflect the damage evolution law of the joints from basically intact to completely destroyed than other damage model and quantitatively determine the damage limit of the joints with different damage levels.Seismic damage of the joints are mainly concentrated at bolt connection of upper and lower flanges of sorghum,and the damage accumulation increases with the increase of loading cycles,the ultimate failure mode is plastic hinge failure of sorghum.The conlusion provides theoretical basis for the damage-based seismic design method and seismic damage assessment of the joints.