Abstract: A reinforcement apparatus for reinforcing a structure comprising at least one pier bearing on foundations, a cross-beam bearing on said pier and at least one structure element located above the cross-beam, the reinforcement apparatus comprising at least one column (20) destined to surround the pier at least partly, to be mechanically coupled to the pier and to bear on said foundations, and at least one transverse beam (22) fixed relative to the column and destined to be mechanically coupled to the cross-beam, and at least one load transfer element (36) arranged on an upper face of said at least one transverse beam (22) to take up at least part of the load of the structure element.