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.