Testing and Noise Assessment of Two Types of Bridge Expansion Joints: Case Study

Expansion joints mounted on the edges of bridges can cause excessive noise and environmental nuisance. Currently, there are no standardized European methods for assessing the noise of these devices. This article presents the results of investigations of two expansion joint devices: a modular one used for small displacements and a finger one used for large displacements. The method proposed in the Austrian standard was used to evaluate the acoustic effects. The exposure levels of the sound were compared after analyzing 100 reliable car passes through each device. Acoustic signals were recorded and analyzed at three points. In the case of the modular device, the average exposure sound level above the device was 2.6 dB higher than the noise above one outside the device. For a finger device, the difference was 1.2 dB. The latter device can be considered “low-noise”. The amplitude–frequency characteristics of the recorded phenomena were also analyzed to show which frequencies are responsible for excessive noise. The dependence of sound emissions on the speed of cars was also determined. The conducted research has shown that the adopted method can be successfully used for the acoustic evaluation of expansion joint devices.