高强度U肋加劲钢板残余应力测试及模拟分析

为研究Q420级高强度U肋加劲钢板纵向焊接残余应力分布特点及影响因素,利用切割法对U肋加劲钢板进行了纵向残余应力测试,通过三维实体热弹塑性有限元模型和单元生死技术模拟了焊缝填充和焊接过程,比较分析了高强度钢和普通强度钢的残余应力分布特点,探讨了母板厚度及U肋的厚度、间距、宽度、高度对加劲板焊接残余应力的影响.研究结果表明,U肋两侧的焊接先后顺序并不影响加劲板的残余应力分布;非焊接区域残余压应力峰值和分布特点与板件材料的屈服强度基本不相关;板件厚度、U肋顶宽和U肋高度是影响高强度U肋加劲钢板焊接残余应力的主要因素.

Experimental and Numerical Analysis of Welding Residual Stress in High Strength U Rib Stiffened Steel Paltes

To study the distribution characteristics and influencing factors of longitudinal welding residual stresses in high strength U rib stiffened steel plates of Q420 grade, the model test of longitudinal residual stresses in U rib stiffened steel plates were measured using the method of sectioning technique. Besides, a 3 D solid thermal elastic plastic finite element method (FEM) was developed by using an element birth and death method to simulate the process of weld filler variation and welding, and the residual stress distribution between high strength steel and common strength steel was analyzed. Furthermore, the effects of flange thickness, U rib thickness, space, width and height on welding residual stresses were studied comparatively. The results show that the welding sequence in bilateral rib has no effect on stress distribution. The longitudinal compressive residual stresses out of weld zone is irrelevant to yield strength. Plate thickness, U rib width and height are the main factors affecting welding residual stresses in high strength U rib stiffened steel plates.