轴力与双向弯矩作用下方钢管焊接球节点的承载力与实用计算方法研究

Load-carrying capacity and practical calculation method of welded hollow spherical joints with square steel tubes subjected to combined axial forces and biaxial bending moments

国家游泳中心“水立方”结构中采用了连接方钢管、且承受轴力与弯矩共同作用的焊接空心球节点。文献[1]系统研究了方钢管焊接球节点在轴力与单向弯矩作用下的承载能力并建立了实用计算方法。本文进一步对轴力与双向弯矩作用下的这类节点进行深入研究。对轴力与双向等弯矩共同作用的节点,通过有限元分析、试验研究以及简化理论解三条途径,系统研究其受力性能,并提出节点承载力的实用计算方法。而对双向任意弯矩作用的情况,提出了对单向弯矩及双向等弯矩两种情况进行线性插值的简化计算方法。

Welded hollow spherical joints connected with square hollow sections are adopted in the National Swimming Center “Water Cube”, which are subjected to combined axial forces and bending moments. The load-carrying capacity and practical calculation method of welded spherical joints connected with square steel tubes under axial forces and uniaxial bending moments have been investigated in Ref. [ 1 ]. Further studies are carried out in this paper on the joints subjected to combined axial forces and biaxial bending moments. For joints subjected to combined axial forces and equal biaxial bending moments, three approaches including finite element analysis, experimental study and simplified theoretical solution are employed to investigate their structural behavior, leading to the practical calculation method for the load-carrying capacity. For joints subjected to arbitrary biaxial bending moments, a simplified method is proposed for the bearing capacity which is based on a linear interpolation between file two limiting cases of uniaxial bending moments and equal biaxial bending moments.