抄録
In order to control Shinkansen wayside noise, various measures along the Shinkansen lines have been made. Around a tunnel portal, the wayside noise tends to be greater. In past studies, the prediction models and countermeasures for the wayside noise around the tunnel portal of Shinkansen line have been investigated. It has been found that (1) the Shinkansen wayside noise around the tunnel portal consists of both noise from open section and noise from tunnel section and (2) the noise is reduced properly by putting sound absorbing materials on an inner wall of tunnel entrance hood. In this paper, in order to develop the prediction model, an acoustic model test were carried out. It was found that the noise radiated from the tunnel portal was affected by vehicles. Then, the prediction model was improved by considering the screen effect due to vehicles in the open section, and the validation work of the model was made.