The method comprises the following steps for each of the reinforcing bands: a) anchoring a first zone (2a, 3a, 4a) of the reinforcing band onto the construction work and establishing a free portion of the reinforcing band; b) tensioning the reinforcing band (2, 3, 4) by applying traction to a second zone of the reinforcing band located in the free portion, said traction causing an elongation (d2, d3, d4) of and a reactive force (R2, R3, R4) in the reinforcing band, with the free portion of the reinforcing band being free to slide on the construction work as it elongates; and c) mechanically attaching the reinforcing band to itself and/or to the construction work, so as to absorb the reactive force from the reinforcing band within a region of the construction work which can support the reactive force from the reinforcing band.