Performance of median noise barriers

摘要

It is possible to incorporate 'median' barriers as a noise control measure on the central reservation of dual carriageway roads. The purpose of this paper is to investigate the performance of these barriers alone, and in conjunction with roadside barriers. A numerical model is used which simulates the traffic as six incoherent line sources of sound. The results for insertion loss show remarkable consistency over a range of receiver prositions. The median barrier produces an insertion loss of about 1dB for propagation above rigid ground and 2dB for grassland. This can be added to the predicted insertion loss of roadside barriers to give the result for the combination.