船体分段焊接变形仿真

船体分段在焊接过程中产生的焊接变形会使船体结构强度降低,然而精确预测和控制焊接变形是个难题.文章提供了准确预测焊接变形的固有应变等效载荷法.这种方法运用有限元法结合固有应变理论以及实验结果对焊接变形进行分析:引入简化的弹-塑性分析杆-弹簧模型,通过分析得到固有应变受焊接区域约束度及最高温度分布情况的影响;将固有应变转化为等效载荷,应用弹性有限元分析求得整个结构的焊接变形.计算结果与LEECH计算及实验结果吻合较好.

Simulation of welding deformations of ship sections

Deformations of welded ship sections reduce the strength of ship structure. However, it is difficult to accurately predict and control the welding deformations. A method, the equivalent loading method based on inherent strain, to predict welding deformations of structures accurately is presented in this paper. The method uses FEM combining the inherent strain theory and the experimental results for analysis. A simplified elastic plastic analysis model, bar-spring model is introduced to the method. By the analysis, the influence of the degree of restraint in the welded region and the highest temperature distribution on the inherent strains is gained. Then the inherent strains are changed into equivalent loads. The deformations of the whole structure are calculated by elastic FEM. The results have good coincidence with those of LEE C H and the experiment.