Abstract: This invention relates to a tridimensional structural element which can be composed with similar elements or with other components to obtain constructions, and particularly coverings having low weight and high resistance. In order to obtain the highest possible static resistance, the best working conditions in whatever possible application and the possibility, without the need of any sliding part, of absorbing thermal expansions, the structural element according to the invention comprises a first body having an essentially polygonal plane surface and an even number of sides, i.e., six or more than six, as well as a series of bodies each having an essentially triangular plane surface, which derive towards the outside from alternate sides of the first polygonal body and are on planes forming angles to one another and with respect to the polygonal body plane, in such a way that all the theoretical vertices of the bodies simultaneously touch the surface of a curved surface.