部分车辆成组的多车道混合车流噪声的计算机模拟

本文给出一种一次性综合模拟多车道多车种随机车流噪声的计算机模拟的简化方法,详细推导了用于预报部分车辆成组行驶的随机车流噪声的数学模型(M₂模型)的车头时距分布函数、概率密度函数和平均时距表达式及相应的随机数变换式。文中还给出了计算机程序框图,并将M₂模型模拟结果与据车头时距为负指数分布的M₁模型的模拟结果作了比较。计算机程序是根据我国交通噪声测量统计方法编制的,只要在程序中输入车流量、车流成份,测点离各车道及等效车道的距离诸参量,计算机便能自动输出L₁₀、L₅₀、L_eq等声级值。预报值与实测值良好一致。

A COMPUTER SIMULATION MODEL FOR PREDICTING NOISE LEVELS FROM A COMPLEX VEHICLE STREAM ON A MULTI-LANE STREET WITH SOME VEHICLE BUNCHES

In this article, a simple computer simulation method for synthetically predicting the statistical noise levels from a random complex traffic stream on a multi-lane street is presented. The probability distribution function, promability density function and the expectation of successive headways of a computer model (M₂ model) which can simulate the complex traffic stream with some vehicle bunches are derived in some details. The transformation formula producing the random numbers that obey this distribution is also derived. Then the simulation flow chart is given. A comparison between the simulation results based on M₂ model and M₁ model (exponential distribution model) is made. The simulation pragram is worked out according with the standard method of measurement of road traffic noise in China. The traffic volume, traffic component and the distances between observer and equivalent lane and each lanes are fed into the computer, then the statistical nodse levels, such as L₁₀ and L₅₀ Legwill be printed out. The calculation show that simulation data agree with practical data well.