A structural element, including a base portion and a connecting central pin, has its base portion formed hallow, and having an internal reinforcement in the shape of WOW or MOM, to connect these elements with an insertable central pin so that the cross-section of the pin corresponds to the shape of the chamber between the reinforcements, when the upper surface of the structural element has longitudinal grooves, and is made from a modified polymer or elastomeric material comprising India rubber mixtures. The foundation is monomer ethylene propylene diene or natural rubber or styrene-butadiene rubber and/or combinations of the natural rubber/styrene-butadiene rubber, or thermoplastic elastomers, whose base is monomer ethylene-propylene-diene or polypropylene/monomer ethylene-propylene-diene or polyvinylchloride, or thermoplastic vulcanizates, whose base is monomer ethylene-propylene-diene and polyethylene or natural and/or synthetic rubber, modified by polyethylene or polypropylene.