A system for stiffening a structure has at least one pair of tie rods (3), each tie rod (3) of the pair of tie rods (3) having a first end (4) fastened to the structure (2) and a second end (5), and at least one device (6) for tensioning the tie rods (3) having a deformable linking element (7) fastened to the second end (5) of each tie rod (3) so as to connect the tie rods (3). An actuator (10) is configured to deform the linking element (7) so as to make it pass from an inactive configuration in which the tie rods (3) are in a first state of tension to an active configuration in which the tie rods (3) are in a second state of tension, different than the first state of tension.