Method for producing a reinforced concrete part, and thus-produced part

A method for producing a reinforced concrete part (1) comprising, a step of molding concrete around at least one tensioned longitudinal bar (21) to form a reinforced concrete part, on either side of a neutral line (10), a compressed portion (C) and a tensioned portion (T) subjected to tensile stresses and having a tendency to elongate under the effect of the load supported by the part, and in which is embedded a reinforcing frame (2) comprising, in the tensioned portion, said at least one tensioned longitudinal bar (21) securely attached to the concrete by an adhesion link determining, along said tensioned longitudinal bar (21), a tangential adhesion stress varying according to the tensile stresses applied, respectively, to the tensioned longitudinal bar (21) and to the coating concrete (16), an increase in the tensile stress in the concrete above a limit value causing at least one crack (3) to open with a transfer of the tensile stress to the tensioned longitudinal bar (21) and a corresponding elongation thereof, at least in the most stressed portion of the part,

• said tensioned longitudinal bar (21) consisting in a discontinuous series of spaced blocking areas (25), each blocking area (25) comprising a plurality of anchoring means (23), the blocking areas (25) being separated from one another by slippage areas (26) with no anchoring means, the blocking areas and slippage areas being integrally formed in the tensioned longitudinal bar (21),
• wherein said slippage areas (26) are shorter than said blocking areas (25), and
• wherein each blocking area extends over a length that is at least equal to a sealing length (l0) of the tensioned longitudinal bar (21) determining an adhesion stress that is at least equal to the maximum tensile stress that is acceptable for the tensioned longitudinal bar (21) and less than twice said sealing length (l0) of the reinforcing tensioned longitudinal bar, each slippage area extends over a length less than a sealing length (l′0) of a smooth bar with equivalent round section, whereby in each of the slippage areas, a local increase in the tensile differential between the tensioned longitudinal bar (21) and the concrete above a limit value results in a detachment of the tensioned longitudinal bar (21) relative to the concrete (16) that coats it, over at least a portion (27) of the length of said slippage area (26) included between two blocking areas (25a, 25′a), said detached portion (27) being able to elongate without disturbing the coating concrete (16) under the effect of the tensile stresses applied to the tensioned longitudinal bar (21).