The Acoustical Design of Structures above or Adjacent to Railroad Tracks

Abstract

Current urban redevelopment trends in both the USA and Canada are resulting in the construction of more and more buildings adjacent to or above railroad tracks. At the present time several such building sites are being developed, the economic success of which is strongly dependent upon how effectively the airborne and structureborne noise, due to nearby heavy freight train activity, is isolated from interior sensitive spaces. This paper reviews what has been done, both architecturally and structurally, to incorporate noise and vibration isolation controls in the source-to-receiver paths on several current projects. The measured performance of a completed structural isolation system that uses neoprene pads is discussed. In addition, data are presented on a recent field evaluation of the quantitative differences between continuous-welded rail and conventional jointed track with respect to both the generation of acoustic noise and the relative levels of ground-induced vibration. Data are also shown which demonstrate how the source noise and vibration levels vary as a function of train speed, car weight, and maintenance condition of the wheels for typical freight traffic.