高轴压比CFST柱-组合梁单边螺栓节点抗震性能分析  

Seismic Behavior Analysis of Single Side Bolt Joint of CFST Column-Composite Beam Under High Axial Compression

作　　者：丁发兴[1] 罗开源 雷建雄 吕飞 DING Fa-xing;LUO Kai-yuan;LEI Jian-xiong;LYU Fei(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《东北大学学报(自然科学版)》2024年第12期1787-1797,共11页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(51978664)。

摘　　要：对9个钢管混凝土(concrete-filled steel tubular,CFST)柱-组合梁单边螺栓节点开展三维实体有限元精细化模型抗震性能分析,其中采用混凝土三轴塑性-损伤和钢材混合强化-韧性损伤模型,探讨了拉筋、轴压比、梁高、加劲肋对节点抗震性能与破坏形式的影响规律,结果表明钢材引入韧性损伤的有限元模型分析结果与试验结果更加吻合,且增加端板加劲肋和增大钢梁高度均能大幅提高节点刚度、承载力和耗能能力.探究不同钢梁尺寸和柱内拉筋强构造对钢管混凝土柱-组合梁单边螺栓节点承载力、刚度和塑性耗能分配与失效机制的影响规律.分析结果表明:拉筋大幅提升了柱端抗弯承载力和耗能能力,使得节点在轴压比为0.8时仍维持梁端失效模式;节点梁-柱抗弯承载力比介于1.57~2.04时将由梁耗能向柱耗能转变.因此对于栓连螺栓组合节点强柱弱梁的判定,建议梁-柱抗弯承载力比值由1.0提升至1.5.A three-dimensional solid finite element model is used to analyze the seismic performance of 9 CFST(concrete-filled steel tubular)column-composite beam single side bolt joints.The concrete triaxial plastic-damage and steel mixed reinforcing-toughness damage models are used to discuss the effects of tensile reinforcement,axial compression ratio,beam height and stiffener on the seismic performance and failure forms of the joints.The results show that the finite element model of steel with ductile damage is more consistent with the test results,and the increases of the end plate stiffener and the steel beam height can greatly improve the joint stiffness,bearing capacity and energy dissipation capacity.Then,the effects of different steel beam sizes and reinforcement structures on the bearing capacity,stiffness and plastic energy dissipation distribution and failure mechanism of concrete-filled steel tubular column-composite beam unilateral bolted joints are investigated.The analysis results show that the tensile reinforcement greatly improves the flexural bearing capacity and energy dissipation capacity of the column end,making the joint maintain the failure mode of the beam end when the axial compression ratio is 0.8.When the joint beam-column bending capacity ratio is between 1.57 and 2.04,the beam energy dissipation will change to column energy dissipation.Therefore,according to the definition of strong column and weak beam,it is suggested to raise the ratio of beam to column flexural bearing capacity from 1.0 to 1.5 for this kind of joint.

关 键 词：钢管混凝土柱 拉筋 螺栓连接 有限元分析 抗震性能 

分 类 号：TU398.9[建筑科学—结构工程] TU352.11