【摘要】 对于在复杂分布随机动载荷激励下,结构的动响应计算问题,目前现有的计算方法效率低下,给工程计算带来诸多不便。提出一种新的快速算法,首先将分布随机动载荷互功率谱函数利用二维勒让德正交多项式在正交域内进行分解,用有限的参数信息表示无穷的分布信息,把分布随机动载荷的动响应计算转化为确定性分布动载荷的动响应计算,对每一个频率点通过向量乘法计算得到响应的功率谱。将该快速算法与常规算法进行仿真比较,得出该快速算法是求分布随机动载荷的精确算法,计算效率大大高于常规算法,而且很方便的计入分布随机动载荷部分相干的效应。最后将该种算法编制成计算软件,结合有限元软件用于分布随机动载荷的计算。更多还原

【Abstract】 Low-efficiency of current algorithm for calculating frequency domain response of structure,subjected to complex distributed random load,leads to inconvenience of engineering application.A new fast algorithm was introduced to solve the above problem.The cross power spectrum function of distributed random load was expanded by two-dimensional Legendre polynomials,and the infinite distributed information was expressed by finite parameters.Then the dynamic response computation under distributed random load was transformed into that under distributed harmonic load.The response power spectrum at each frequency point was obtained by vector multiplication.Compared with the regular algorithm,it can be concluded that the fast algorithm is accurate,and its efficiency is much higher than that of the regular algorithm.Moreover,it is convenient to consider the coherences of distributed random load.Combined with the software of finite element analysis,a computation software including the fast algorithm was compiled for computation of distributed random load.更多还原