钢管混凝土T型节点在平面内弯曲荷载作用下的静力强度研究

Static Strength of Concrete-Filled Circular Tubular(CFCT) T-joint under In-Plane Bending Load

利用有限元软件ABAQUS分别对空心截面T型管节点和主管中填充混凝土T型管节点在支管端部平面内弯曲荷载作用下的静力强度进行了研究.有限元模型的可靠性通过已有文献中的圆钢管混凝土N型管节点的试验结果进行了验证.利用有限元模型分别对3个主管中未填混凝土和3个主管中填充混凝土的T型管节点的静力强度进行分析.结果表明,主管中填充混凝土能显著的提高管节点的抗弯承载力.在此基础上,对钢管混凝土T型节点进行参数分析,参数包括支主管直径比β,主管直径与2倍主管壁厚比γ,支主管壁厚比τ,钢材屈服强度fy和混凝土的抗压强度fc.分析表明,参数β,γ,τ和fy对T型节点抗弯承载力有显著影响,而混凝土的抗压强度fc对节点的承载力影响不大.

The static strengths of circular hollow section ( CHS ) tubular T-joints and corresponding T-joints with concrete filling in the chord member under in-plane bending load at the brace end are investigated by using finite element analysis software ABAQUS. The finite element model is firstly verified by comparing the predicted results with reported experimental results on concrete-filled circular tubular ( CFCT ) N-joint. Thereafter, the static strengths of three CHS T-joints and three CFCT T-joints are analyzed using the verified model. The numerical re-sults show that concrete filled in the chord member can significantly improve the flexural capacity of the joints. Fur-thermore, parametric analyses on CFCT T-joints are conducted. The parameters include brace-to-chord diameter ra-tio β, chord diameter-to-wall thickness ration γ, brace-to-chord wall thickness ratio τ, yield strength of steel fy , and strength grade of concrete fc . The results indicate that the parameters of β,γ,τ and fy have significant effect on the static strength of CFCT T-joints. However, the effect of the strength grade of concrete fc is minor.