Tire reinforcement (10) having a bi-material structure of reinforcing elements that consists of at least a plurality of extensible first reinforcing elements (1) and at least a plurality of inextensible second reinforcing elements (2), these first and second reinforcing elements being mutually parallel and distributed alternately in appropriate proportions in order to achieve the desired level of reinforcement, these first and second reinforcing elements lying within the same mean plane, this reinforcement being such that the extensible first reinforcing elements (1) are coupled to the inextensible second reinforcing elements (2) over a coupling length Lc which is shorter than the length L1 of the extensible first reinforcing elements (1) so that, with each of the first and second reinforcing elements having two ends, at least one of the ends of the extensible first reinforcing elements (1) is offset in relation to the two ends of the inextensible second reinforcing elements (2).