基于MIGA的结构模型修正及其应用

为了寻找到优化域内的全局最优解,获得更准确的结构有限元模型,提出将多岛遗传算法(MIGA)应用到模型修正中,以响应面替代模型简化有限元计算分析,以有限元理论分析模态与结构实测模态残差为目标优化函数.在参数灵敏度分析的基础上,建立桥梁结构动力响应、单元弹性模量、密度以及截面面积的优化数学模型,采用MIGA作为优化策略,对桥梁结构进行了动力测试和模型修正.结果表明,模型修正效果良好,可真实反映结构的动力学特性,证明了该方法的有效性和可行性.

Structure Model Updating Based on MIGA and Its Application

In order to find the global optimal solution and obtain more exactable finite element model,model updating is carried out by using multi-island genetic algorithm(MIGA).Taking the residual error of the numerical and field-measured structure response as objective optimization function,an optimal mathematical model is set up,which refers to the dynamic response of bridge structure,element elasticity modulus,density and dimension of the element cross section.The MIGA is adopted as optimization policy.Simulation example of a bridge model is used to demonstrate the method.The result shows that the proposed method works well and the updated model represents the dynamic property of the structure availably,which demonstrates its feasibility and validity.