USING A BOUNDARY ELEMENT APPROACH TO STUDY SMALL SCREENS CLOSE TO RAILS

A boundary element program based on a variational approach is used to study the efficiency of small screens placed very close to the rails, in addition to a normal full-size noise barrier. Seven dipoles represent the noise generated by the sleepers, the wheels and the rails. In order to reduce the noise emitted by these sources the screens must be absorbent. Further noise reduction is achieved by adding some absorbing material under the car.