斜交网格X型节点轴压承载力性能研究

Investigation of axial bearing capacity of X-nodes in diagrid structures

采用ABAQUS分析软件对斜交网格X型节点进行轴压荷载作用下的非线性分析,依据轴压荷载作用下节点各组成部分的应力分布情况及钢管混凝土短柱工作机理和Mises屈服准则,提出了该类型节点的承载力计算公式.同时,以相贯角度、宽厚比、竖向连接板厚度、衬板厚度、混凝土强度、加强环厚度等为控制参数,分析其对斜交网格X型节点承载力及公式适用性的影响.研究表明:采用竖向连接板、衬板、加强环较好的改善了对节点区混凝土的约束作用;相贯角度、宽厚比、混凝土强度对节点承载力影响较大,竖向连接板厚度、衬板厚度、加强环厚度对承载力影响相对较小;计算公式的参数选取合理,计算值精确度较高,可用于工程中构件承载力的计算.

Analysis software of ABAQUS is used in nonlinear analysis for X-nodes of diagrid structures under axial compression load. The calculation formula of bearing capacity for the nodes is proposed based on the stress distribution of each component of the nodes under axial compressive load, the working mechanism of concrete-filled steel tubular short columns and the yield criterion of Mises. Then, according to the controls parametric of intersecting angle,width-thickness ratio, thickness of vertical connecting plate and lining p late, concrete strength and thickness of stiffening ring, the effect on the applicability of the calculation formula and the bearing capacity for the X-nodes of diagrid structure was analyzed. The research shows that the vertical connecting plate,lining plate and stiffening ring of the nodes could all improve the confinement effect of concrete. The parameter of calculation formula of bearing capacity is reasonable and the precision of calculated results is high. Intersecting angle,width- thickness ratio and concrete strength all have great influence on the bearing capacity of the X-nodes？ while thickness of vertical connecting plate,lining plate and stiffening ring have little influence on the bearing capacity of the X-nodes.