VEHICLE OPERATION AND ROAD TRAFFIC NOISE REDUCTION

The relationships between vehicle speed and traffic noise are examined. The influence of traffic management on noise levels is discussed. Research has shown that after the installation of road humps and cushions the maximum noise levels from cars are reduced, but decreases in maximum noise levels from large commercial vehicles can be offset by increases in noise from vibration. Narrower cushions offer a better acoustic performance than wider cushions as the proportion of large commercial vehicles increases. The influence of tyre and road surface design on noise is considered with reference to the introduction of tyre noise type approval, the TRITON road and tyre noise measurement system. The relationship between driver behaviour and noise emission is discussed. Research has shown that noise emission can be reduced by encouraging drivers to drive passively rather than aggressively.