Abstract: The element comprises a socket and a bar slidingly insertable into the opening of the socket. Disposed around and spaced from both the socket and the bar are at least two closed loops each, of generally rectangular shape and made from reinforcing rods. The loops are secured to the socket and the bar, respectively, in one case by welding, in another case by means of a holder. Because they are symmetrically spaced from the socket and the bar, they ensure good distribution of pressure within the concrete.