Traffic noise and vehicle movement at a controlled intersection

Traffic noise at an intersection controlled by traffic lights shows noise level variations due to the alternating green and red lights for the different traffic streams. Noise peaks caused by automobiles pulling up or passing by at high speed may be quite annoying for people living near the intersection. Detailed prediction of the variations is difficult, primarily because of the complexity of the traffic flow on the intersection. In this article an experimental study is presented of traffic noise near an intersection controlled by traffic lights. Sound measurements were performed at the facade of an apartment building near the intersection. Vehicle tracks and other traffic data were derived from a wide-angle video recording of the intersection during the noise measurement. The video recording was also used to generate a differential image of moving vehicles, from which an overall “vehicle movement level” that correlates well with the measured noise level was derived. An interesting consequence of this observation is that video recordings can be used for focused real-time monitoring of traffic noise levels. Further, calculated noise levels were determined with the Dutch standard traffic noise model, based on the vehicle tracks. The calculated level shows good agreement with the measured level, except for some peaks generated by noisy vehicles exceeding the speed limit of 50 km/h. The potential effect of strictly enforcing the speed limit is analyzed.