【摘要】 利用从发射台骨架试验模型获取的模态参数,选择识别结果中精度较好的模态频率作为模型修正的基准频率。通过对待修正参数的灵敏度分析,运用ANSYS和MATLAB软件对有限元模型进行了修正。以实测模态和计算模态之间的误差建立一个带约束边界的非线性最小二乘目标函数,将损伤识别问题转化为优化问题,引入量子遗传算法处理模态参数,进行结构的损伤识别。为了让量子遗传算法更适用于结构工程损伤识别领域,提出了改进的动态策略调整量子门旋转角。以有限元模型焊接结点单元组弹性模量的降低模拟焊缝损伤,并假定了损伤工况,对发射台骨架模型的数值仿真及试验研究表明:该损伤识别方法识别效果较为理想,为解决这种复杂焊接结构焊缝损伤识别问题提供了新的思路。更多还原

【Abstract】 The identified frequencies which were more accurate were selected as updating parameters.Then the initial finite element model was modified by ANSYS and MATLAB based on sensitivity ana-lysis.A nonlinear least-squares objective function with bound-constrains was determined by minimizing the error between the experimental and analytical modal modes to bring damage detection into optimization with this method.The quantum genetic algorithms were used to deal with the model para-meters for structural damage detection.The improved dynamic adjustment strategy was introduced to adjust the quantum rotation corner.Finally,the proposed method was applied to damage detection on the frame of a launch platform.The elastic modulus reduction of jointing crunodes elements group was taken to simulate the weld seam damage and two cases were investigated.The simulation and experiment results show that the proposed method is well suitable for weld seam damage detection of such complex steel tube welded structures.更多还原