Mechanism and reduction countermeasure of structure borne sound of reinforced concrete viaducts

Abstract

We have developed a new analysis method to analyze effectively the vibration response of the structural members of railway reinforced concrete viaducts. In this paper, numerical experiments to investigate the structure borne sound countermeasures were conducted for high-speed train operation over 320 km/h, considering structure vibration of reinforced concrete rigid frame viaducts. Numerical experiments with the vehicle/track system model were carried out using the program DIASTARSIII developed by Railway Technical Research Institute, which can analyze dynamic interaction between vehicle and railway structures. Furthermore, numerical analysis with the track/structure system model was carried out using the program DIARIST. As a result, we proposed various countermeasures for structure borne sound and quantified their vibration reduction. First, reinforcements of center slab and cantilever slab are effective. Second, vibration reducing track is more effective than softening of the rail pad spring constant. But, the frequency range where reduction effect can be obtained depends a great deal on natural frequency of vibration reducing track. Third, vibration reduction effects by adjusting vehicle parameters are smaller than those by adjusting structure and track parameters in consideration of the feasibility of reduction a vehicle mass.