【作者】 曾骥；

【导师】 任慧龙；

【作者基本信息】 哈尔滨工程大学 ， 船舶与海洋结构物设计制造， 2004， 硕士

【摘要】 焊接变形是焊接结构制造过程中最常见的问题之一。焊接变形不仅影响船体的外观，而且降低了结构的强度性能。此外，焊接变形还会导致结构出现装配误差，从而影响生产率。本文研究了一种基于固有应变理论的预测复杂结构焊接变形的有限元法分析方法，主要内容有： 1)针对不同焊接接头形式和不同焊接方式并考虑焊道及坡口的影响，给出了计算沿焊缝方向线能量的方法。重点阐述了几种主要变形形式的产生机理并分析了有关参数的影响。 2)探讨了固有应变与焊接变形的关系，推导了固有应变的简化计算公式。通过分析各种船用材料的温度特性，讨论了有限元计算中考虑材料非线性的弹性模量的取值。 3)给出了平板堆焊和加筋板角接焊结构的固有应变区大小的计算方法，并探讨了计算约束弹性系数的方法。然后将固有应变进行积分得到焊缝边缘的等效载荷。 4)总结了应用固有应变等效载荷法预测焊接变形的过程，对平板堆焊和加筋板焊接等结构形式进行了计算并与有关文献进行比较分析。分析结果表明，本文讨论的方法是一种计算大型复杂结构焊接变形的有良好发展前景的工程实用方法。更多还原

【Abstract】 Welding deformation is one of the most common problems in the structural manufacturing process. Welding deformations injure the beauty of appearance of a structure and decrease its strength capability. In addition, welding deformations cause errors during the assembling of the structure and prevent increase of productivity. A kind of finite element analysis method based on inherent strain theory to predicate the welding deformation of the complicated structure is studied in this thesis. The main contents are as follows:1) A method of calculating the heat input of unit length in the direction of welding line for various welding joints and welding facilities is presented with the influence of the bead and groove being considered. The mechanism of production of main deformation modes are demonstrated .and the effects of relevant parameters are analyzed.2) The relationship between the inherent strain and welding deformation is discussed and the calculating formula of the inherent strain is derived. The value of the nonlinear elastic module is discussed in the finite element analysis, through analyzing the temperature-dependent properties of various naval materials.3) The method to calculate the dimensions of the inherent strain region of the bead on plates and stiffened panels is put forward. The calculating method of the restraint coefficients is discussed. The equivalent loads of welding line region are derived by the integration of inherent strain.4) The process of predicting welding deformations with FEA method based on the above mentioned equivalent loads is summarized. The deformations of plates and stiffened panels are calculated and compared with the results in the relevant references. The conclusion show that the method presented in this thesis is practical and prospective.更多还原