运用数值迭代的动载荷识别算法

An algorithm of dynamic load identification based on numerical iteration

Wilson-θ法作为一种常用的数值算法,参数设置合适时,能够保证计算结果绝对收敛,根据这一特性可以推导得出其反分析法。然而从实际算例计算结果来看,这种反分析方法并不稳定。指出了Wilson-θ反分析法发散的原因,针对这个问题提出了一种利用二分法原理的迭代修正算法。利用步步修正的思想,消除累积误差,增加了算法的稳定性。在此基础上,进行了数值仿真和实验研究,结果表明该方法具有良好的收敛性和抗噪能力。

Wilson-θmethod is one of the commonly used numerical algorithms,where the properly set parameters can usually result in absolute convergence of the solution.Based on this characteristic,a retrospective method of load identification can be derived by employing this theory inversely.However,from the calculated results of practical examples,it is shown that the method is not a kind of stable algorithm.The paper indicates the reason why the inverse wilson-θmethod will diverge and put forward an corrective iterative algorithm using the principle of bisection.The step-by-step corrective method is used to eliminate cumulative errors and improve the stability of the algorithm.Numerical simulation and experimental research have been carried out for several cases,of which the results show good convergence and anti-noise capability of this method.