为了更加直观有效地描述路面平整度,提出了一种路面平整度的模拟方法,即随机正弦波法.该方法将路面平整度表示成大量具有随机相位的正弦或余弦之和,采用离散谱逼近目标随机过程,是一种离散化数值模拟路面平整度的方法.根据给定的路面功率谱系数,在时域路面随机位移输入的频率特征与给定的路面谱相一致的情况下,通过计算机模拟将路面平整度优化成为随机振动的等效信号,得到各等级下路面的平整度曲线.结果表明:随机正弦波法适用于实测道路谱的时域模拟,由于该方法数学推导严密,使用范围广泛,且模拟曲线直观,对于汽车平顺性研究具有十分重要的意义.最后,提出一个与路面功率谱系数相关的平整度指标——名义平整度指数. In order to describe the degree of pavement more intuitively and effectively, a method of simulating pavement roughness is proposed, which is called random sine wave method.The pavement flatness is expressed as the sum of a large number of sine or cosine with random phase, and the discrete spectrum approach Target stochastic process is a method of discrete numerical simulation of road surface roughness.According to given PA power spectrum coefficient, when the frequency characteristics of stochastic displacement input in time domain road surface are consistent with the given road surface spectrum, The simulation results show that the random sine wave method is suitable for the time domain simulation of the measured road spectrum because of the mathematic derivation of the method and the application range It is very important for the study of car ride comfort.Finally, we present a flatness index - the nominal flatness index related to the road power spectral coefficient.