Numerical and experimental assessment of advanced concepts to reduce noise and vibration on urban railway turnouts

The short service life of rail turnouts and the related noise and vibration disturbance, are directly related to their dynamic distress. Especially in the case of urban rail systems, such problems are amplified due to the increased train frequency and the proximity to inhabited structures. This paper presents three new concepts for the reduction of noise and vibration produced by railway turnouts in urban railway lines, and provides an assessment of their performance. The effectiveness of the three new concepts is first evaluated analytically, using two different methodologies, earlier validated against line measurements on existing turnouts. Then, the actual performance of one of the three concepts, along with the effectiveness of the two analysis methodologies, is verified through real-scale measurements. Based on the presented analyses, all three new concepts are shown to provide a substantial enhancement of turnout performance. Furthermore, soil conditions and soil-structure interaction are shown to play an important role in the behavior of the investigated systems.