A THEORETICAL APPROACH OF THE EQUIVALENT SOURCES METHOD APPLIED TO NOISE BARRIERS

SEBASTIAN PÂRLAC¹, CONSTANTIN ONESCU¹, ION IORGA SIMĂN²,
IOAN ŞTEFĂNESCU³

¹University of Piteşti, Department of Applied Mechanics, 110040, Piteşti, Romania,
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²University of Piteşti, Department of Physics, 110040, Piteşti, Romania, This e-mail address is being protected from spambots. You need JavaScript enabled to view it
³National Institute of Cryogenics & Isotopic Technologies, 240050 Rm.Valcea, Romania, istef@ icsi.ro

 ABSTRACT

The main contribution of noise levels in cities is today road traffic. The strongest source for all road vehicles is most often the tyre-road contact. This source position close to the ground is fortunate with respect to secondary noise abatement measures, such as absorbing road surfaces or noise barriers.
In this paper the equivalent sources method (ESM) is shown to be applicable to a noise barrier problem. The insertion loss can be significantly improved through optimization. To optimize a barrier’s insertion loss for a given height by modifying the boundary conditions is difficult with existing methods. By using the (ESM) such an optimization can be performed in a straight-forward manner. The amount of improvement depends on barrier geometry, the impedance of the surrounding ground and on the frequency.
Keywords: Traffic noise, noise barrier, insertion loss, optimization, equivalent sources method (ESM), boundary element method (BEM).