基于盲孔法的焊接空心球节点网架中无缝钢管表面残余应力的测试研究

Test and Research on Residual Stress of Rolled Tube and Hollow Ball of Cross Plate Welded Hollow Spherical Joints in Grid Structure Based on Blind Hole Method

摘要: 基于盲孔法对同种规格的三个焊接空心球节点无缝钢管表面残余应力进行了试验测量，根据Kirsch理论解计算了本次试验选取的应变片的应变释放系数。依据Scara-Mangas经验公式对计算得到的球面径向、环向残余应力进行塑性修正，最终得出钢管焊趾附近以及远离焊趾表面残余应力分布图。探讨了钢管焊趾附近以及远离焊趾表面残余应力对工程领域中节点强度、疲劳的影响。

Abstract: Based on the blind hole method, the residual stress on the surface of three welded hollow spherical joint seamless steel tubes of the same specification was experimentally measured, and the strain relief coefficient of the strain gage selected in this experiment was calculated according to Kirsch’s theoretical solution. According to the Scara-Mangas empirical formula, the calculated radial and hoop residual stresses of the spherical surface are plastically modified, and finally the residual stress distribution diagrams near the toe and away from the toe of the steel pipe are obtained. The effects of residual stresses near the welded toe of the steel pipe and away from the welded toe on the strength and fatigue of joints in the engineering field were discussed.