Computation Model for Structure-Borne Noise from Railway Bridge with CLD

TLDR: In this paper, a theoretical model for calculating the vehicle-induced vibration and noise of a railway bridge with constrained layer damping is presented, which can achieve an obvious reduction of the treated structure in a wide frequency range by dissipating the vibration energy owing to damping layer deformation.

Abstract: With the increase of running speed and axel load of trains, the structure-borne noise emanating from the railway bridges is more and more serious. The constrained layer damping can achieve an obvious reduction of vibration and noise of the treated structure in a wide frequency range by means of dissipating the vibration energy owing to damping layer’s shear deformation. Based on the train-track-bridge coupled vibration, modal strain energy method and statistical energy analysis, a theoretical model for calculating the vehicle-induced vibration and noise of the railway bridge with constrained layer damping is presented. The vibration and noise of the (32 + 40 + 32) m steel-concrete composite bridge before and after constrained layer damping installation is simulated. The structure-borne noise radiated by the bridge in the whole analysis frequency range is reduced significantly. The sound pressure level at the field point which is 30 m to the track centerline in horizontal direction and 1.5 m to the ground in vertical direction is reduced by 4.3 dB(A).