Construction plate for acoustic protection at exit from underground roads

摘要

The acoustic plate has several elementary cells (Cn) arranged in a geometric network. Each cell has a central opening surmounted by a tile (Bn) which allows modifying the propagation conditions of transmission or reflection of incident sound waves on the sides opposite the tiles. All the cells are in the plane of the plate and of identical shape. The tiles have a different height perpendicular to the plate as a function of the position of each cell or group of cells in the plate. This allows modulating the transmission pattern of incident sound rays incident.