基于灵敏度分析的大跨桥梁结构有限元模型优化研究

本文给出了一种基于灵敏度分析的大跨桥梁结构有限元模型优化方法。具体步骤如下：（1）通过竣工资料建立有限元模型;（2）利用成桥试验技术报告确定目标函数与修正参数;（3）采用灵敏度分析方法确定修正参数与目标函数的关系,将结构的有限元模型优化问题转化为数学模型的优化问题;（4）采用线性加权法将多目标优化转化为单目标优化问题,并利用二次规划法进行优化求解;（5）用优化后的结果代入有限元模型计算。采用上述方法对金塘大桥主通航孔桥的结构有限元模型进行优化,结果表明：优化后的计算响应值与实测响应值的误差控制在5%以内,验证了上述方法的实用性。

Optimization Method for the Finite Element Model of Large Span Bridge Structure Based on Sensitivity Analysis

Bringing forward the optimization method for the finite element model of large span bridge structure based on sensitivity analysis. The concrete steps are as follows：（ 1） the finite element model is established by the completion of data;（ 2） objective function and parameter modification are determined by the bridge test technology report;（ 3） the relationship between parameters and objective function is established by method of sensitivity analysis,the finite element model of the structure optimization problem change into an optimization problem of mathematical model;（ 4） using the linear weighted method,the multi- objective optimization change into a single objective optimization problem,and the optimization problem is solved by two quadratic programming method;（ 5）calculated finite element model with the optimized results. The finite element model of the main navigation span of Jin tang Bridge was optimized by updated method,results show that ： the error between the response calculation and the measured response is controlled within 5%,The calculation results prove practicability of the updated method.