Method for producing a series of hollow slabs of concrete prestressed by longitudinal reinforcement bars or strands which are positioned between the cells, at the lower portion of these slabs, on a prestressing bed, having a length in the order of 150 m and a width corresponding to that of the slabs, via which the reinforcement strands are positioned parallel with each other, they are placed individually under tension, in particular using actuators, then the concrete is poured using a specific pouring device which is known per se and which is referred to as a sliding formwork, which is moved continuously along the prestressing bed, the slabs are cut to the desired length and, after the concrete has set, the strands are cut in order to place the concrete in a prestressed state, comprising the following steps: - there are formed lifting and handling loops which are each constituted by a bent metal rod which comprises, on the one hand, at the central portion thereof a central bent portion which defines a planar gripping ring and, on the other hand, at the respective ends thereof, lateral bent portions which extend substantially symmetrically at one side and the other of the central bent portion, the lateral bent portions defining at the ends of the loop positioning lugs (9, 9') which are directly contiguous with substantially U-shaped fixing clips (10, 10') which are located in a plane which is substantially perpendicular to the plane of the gripping ring, and - before the step of pouring the concrete, upstream of the pouring device, in the movement direction of this device, a series of lifting and handling loops are clip-fitted by means of torsion along two lateral strands which are preferably located substantially symmetrically relative to the longitudinal centre axis of the prestressing bed, at one side and the other of these strands, at locations corresponding to the corners of the slabs, so that the gripping ring of each of these loops and the associated strand are substantially coplanar, and in that the positioning lugs (9, 9') thereof are supported on the prestressing bed, and - the concrete is poured so that the central bent portion of the lifting and handling loops is flush, via the upper end thereof, with the surface thereof. - there are formed lifting and handling loops which are each constituted by a bent metal rod which comprises, on the one hand, at the central portion thereof a central bent portion which defines a planar gripping ring and, on the other hand, at the respective ends thereof, lateral bent portions which extend substantially symmetrically at one side and the other of the central bent portion, the lateral bent portions defining at the ends of the loop positioning lugs (9, 9') which are directly contiguous with substantially U-shaped fixing clips (10, 10') which are located in a plane which is substantially perpendicular to the plane of the gripping ring, and - before the step of pouring the concrete, upstream of the pouring device, in the movement direction of this device, a series of lifting and handling loops are clip-fitted by means of torsion along two lateral strands which are preferably located substantially symmetrically relative to the longitudinal centre axis of the prestressing bed, at one side and the other of these strands, at locations corresponding to the corners of the slabs, so that the gripping ring of each of these loops and the associated strand are substantially coplanar, and in that the positioning lugs (9, 9') thereof are supported on the prestressing bed, and - the concrete is poured so that the central bent portion of the lifting and handling loops is flush, via the upper end thereof, with the surface thereof.