平地机作业负载谱分析

Analysis on Load Spectrum of Grader

分析平地机工作装置零部件疲劳特性,基于MATLAB随机函数RANDN、RANDI和RANDPERM,对实际工况载荷进行拟合与仿真,利用雨流计数法简化随机载荷,提取雨流循环,并假设幅值服从威布尔分布,均值服从正态分布,构建平地机二维载荷谱。结果表明,仿真随机载荷与实际载荷近似等价;幅值与均值的分布假设成立,且二者相互独立;参数估计表明国外作业工况随机变化较大。

The fatigue characteristics of the components of grader＇s working mechanism were analyzed. The load of grader in actual working conditions was simulated based on RANDN, RANDI and RANDPERM, the random functions of MATLAB. Rainflow-counting algorithm was applied to simplify the random load, and rainflow cycle was extracted. An assumption was made that the amplitudes follow the Weibull distribution, while the mean values follow a normal distribution, based on which the two-dimensional spectrum for grader was built. The results show that the simulated random load is approximately equivalent to actual load; the assumption is proven to be true, and the amplitude and mean value are mutually independent; the results of parameter estimation show that the working conditions in foreign countries are more stochastic.