内置CFRP圆管的方钢管高强混凝土柱-钢梁节点的静力性能

目的通过研究找出两类内置CFRP圆管方钢管高强混凝土柱-钢梁节点在单调荷载作用下的传力机制和破坏模态．方法设计了一栋采用内置CFRP圆管的方钢管混凝土柱的5层框架结构，利用有限元软件ABAQUS建立了三维有限元模型，对两类节点进行了单调荷载作用下的模拟分析．结果外加强环式节点的梁端弯矩主要通过柱角附近的水平环板和柱两侧外伸环板传递给柱壁和核心混凝土，水平环板有效宽度大约为0．5倍的柱宽度．外肋环板式节点的极限位移均大于外加强环式节点，尤其是外肋宽度大于40mm时更为明显．外肋环板式节点的极限承载力也高于外加强环式节点．结论设计节点的破坏主要原因是环板和钢梁翼缘交接位置出现局部屈曲，节点的极限承载力取决于梁的抗弯承载力，变截面位置作为整个节点危险部位，在设计中应进行计算和校核．

Static Analysis of Joints between High-Concrete Filled Square Steel Tubular Column with Inner CFRP Circular Tube and Steel Beam

This paper studied mechanical behaviors and damage modes of two kinds of joints between high- concrete filled square steel tubular column with inner CFRP circular tube and steel beam under monotonic loading. A concrete frame structure with five layers was designed, based on the square steel tubular column with inner CFRP circular tube. A 3D finite element model was built with ABAQUS and simulations of two kinds of joints under monotonic loading were carded out. It is shown that through level ring plate and the ring plate of both sides of column, the beam end bending moment of enforced loop joint transfers to the cylindrical wall and the core concrete. The effective width of level ring plate is about 0.5 times of the column width. The ultimate displacement of the external rib ring plate joint is larger than that of the enforced loop joint, which is more significantly, when the external rib width is large than 40 mm. The ultimate bearing capacity of external rib ring plate joint is also higher than that of enforced loop joint. It concludes that the local buckling in the transition zone between annular plate and flange of steel beam is a main reason of damage in the designed joints. The ultimate bearing capacity of the joint depends on the flexural capacity of beam. The variable section as a whole joint dangerous position should be calculated and checked clearly in the design.