X型矩形管斜插板节点轴压性能试验研究

Experimental study on compressive property of rectangular tube-skewed gusset X-joints

对X型矩形管斜插板节点在插板轴压力作用下的极限承载性能进行单调加载的试验研究。实施10个不同插板的厚度和插板平面与矩形管轴线之间夹角的节点轴压性能试验。介绍节点试验方案,描述X型矩形管斜插板节点在插板轴压力作用下的破坏模式,给出荷载-端位移曲线以及节点区域应变强度分布曲线,并将插板相对厚度(插板与矩形管厚度比值)τ、插板平面与管轴线之间夹角θ对节点轴向极限承载力和延性的影响进行讨论。试验研究结果表明:随着夹角θ的增大,节点轴压极限承载力呈增大趋势;θ为0°时,τ值对节点轴压极限承载力的影响很小;其余夹角θ节点试件极限承载力随着插板厚度的增大而增大;节点应变强度最大均发生在插板与矩形管连接的焊缝端部区域。最大应变强度在此区域的分布不同,则节点的破坏模式不同;IIW规范计算公式中未考虑τ值的影响,而试验中τ值对节点极限承载力有很大的影响,所以规范还有待完善,需要进行深入的有限元参数分析。

To study the compressive property of rectangular tube-skewed gusset X-joints under compression,ten gussets with different thickness and gusset- tube angles were tested. The joint failure modes,compression in gusset-general deformation and strain intensity distribution curves were presented. The effect of τ( ratio of thickness of gusset to thickness of rectangular tube) and θ( angle between gusset and rectangular tube) on axial ultimate capacity and ductility of X-joints were also discussed. The experimental results show that the axial ultimate capacity of joints increase with value of θ; However,the axial ultimate capacity of joints keep almost constant when θ = 0°. Maximum strain intensity emerge in the weld region of between gusset and rectangular tube. The distribution of maximum strain intensity is different in different failure mode. As shown in the experiment,the axial ultimate capacity was much influenced by τwhich is ignored in IIW code. So,the code should be corrected and detailed finite element parametric analysis and construction of design formula for compressive ultimate capacity of joints should be conducted.