力学约束是一种有效控制焊接变形的方法。本文基于热弹塑性有限元法，研究船体甲板板架结构在垂向力学约束条件下的焊接变形与残余应力情况，分别计算了结构在无约束和5种垂向力学约束方案下的焊接变形和残余应力，通过对计算结果的对比分析，获得最优方案。研究结果表明，垂向力学约束能使整体和局部焊接变形分别减小27%和48%，对甲板板的中面残余应力影响较小，但对板格局部弯曲应力有一定程度影响。
Mechanical constraint is an effective way to control welding deformation. Based on the thermal elastic-plastic finite element method (FEM), this paper studied the welding deformation and residual stress of a deck grillage under vertical mechanical constraint. The welding deformations and residual stresses of the structure are calculated in an unconstrained case and five vertical mechanical constraint cases. A relatively optimal case is acquired by analyzing and comparing the results of the calculation. The study shows that the global and local distortions of the grillage are decreased significantly up to 27% and 48% respectively by applying vertical mechanical constraint. The vertical mechanical constraint can barely affect the mid-surface residual stresses in the deck plate, while it can influence the local bending stresses to some extent.
2018,40(6): 29-34 收稿日期：2017-07-05
DOI：10.3404/j.issn.1672-7649.2018.06.007
分类号：TG54
作者简介：何昱恒(1992-),男,硕士研究生,主要从事船舶与海洋工程结构焊接数值模拟和结构有限元分析
参考文献：
[1] DENG D, ZHOU Y, BI T, et al. Experimental and numerical investigations of welding distortion induced by CO 2, gas arc welding in thin-plate bead-on joints[J]. Materials & Design, 2013, 52(24):720-729.
[2] FU G, LOURENCO M I, DUAN M, et al. Effect of boundary conditions on residual stress and distortion in T-joint welds[J]. Journal of Constructional Steel Research, 2014, 102(11):121-135.
[3] FANOUS I F Z, YOUNAN M Y A, WIFI A S. 3-D finite element modeling of the welding process using element birth and element movement techniques[J]. Journal of Pressure Vessel Technology, 2003, 125(2):165-172.
[4] DENG D, MURAKAWA H. Prediction of welding distortion and residual stress in a thin plate butt-welded joint[J]. Computational Materials Science, 2008, 43(2):353-365.
[5] 沈济超, 陈震, 罗宇. 船体T型接头分段移动热源焊接模拟[J]. 中国造船, 2014, 55(4):66-72.
[6] SHEN J, CHEN Z. Welding simulation of fillet-welded joint using shell elements with section integration[J]. Journal of Materials Processing Technology, 2014, 214(11):2529-2536.
[7] MATO P, ZDENKO T, ALAN R, et al. Numerical analysis and experimental investigation of welding residual stresses and distortions in a T-joint fillet weld[J]. Materials and Design, 2014, 53:1052-1063.
