The results of modal test included frequencies and mode shapes of specimen in different status and stages, so multiple objective functions were needed for model correction. A method of model correction of Timoshenko beam based on Pareto front was proposed. The model was corrected through global crossover and mutation, solving the noninferior solution set, defining new fitness of individuals and sorting the noninferior solution set according to crowding distance. The results showed that high precision can be achieved by this method and the Pareto front converged at nonconvex shape. Compared to the results of test, the deviation of the first natural frequency of the corrected model was less than 1%, the deviation of the second natural frequency was less than 6% and the mode shapes were in agreement with test.%模态试验结果中包含试件不同状态不同阶次的频率和振型信息,对动特性模型修正时需要建立多个目标函数.提出一种基于Pareto最优的Timoshenko梁模型修正方法.通过全局交叉和变异操作,求解群体的非劣解集,定义新的个体适应度评价方法,并根据拥挤距离对非劣解集进行排序,对动特性模型进行修正.仿真结果表明,采用该方法能够获得较高的精度,Pareto最优前沿收敛,且形状为非凸,与试验结果相比,修正后的模型一阶频率偏差不超过1%,二阶频率偏差不超过6%,振型与试验结果一致.
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