Abstract: This invention relates to the use of composite reinforcements advantageously comprising a thermosetting matrix and a filler in particular in the reinforcing of thermoplastic material or of thermosetting resin, in order to obtain a reinforced structure such as a bathtub, a washbasin, a wall panel or a shower tray. This invention relates more particularly to a method for preparing a reinforced structure using composite reinforcements, as well as the structure able to be obtained by such a method.