Abstract: The invention relates to a support structure of a cover of a structure capable of being inserted into the ground, for example of a shaft or a channel, wherein the cover (10) comprises a traversable surface (11) and the support structure (20) extends downwards under said cover into the structure and comprises beam-shaped supports (21-23) such that their under support side (24) facing away from the surface (11) experiences a tensile stress when the surface (11) is loaded. The invention is further characterized in that between two areas (A, A?) a thickness (D) of the carriers with minimum tensile stress is configured substantially symmetrically in an increasing manner up to a maximum value and then, in turn, in a decreasing manner to form a ball shape when viewing the cover from below.

Abstract: A stable and variable design of a drainage structure includes a drainage body (11) and a cover (20). The cover (20) has engagement devices (13, 13?; 14, 14?; 23, 23?) when seen in a longitudinal direction of the drainage body (11), whereby the cover connects upper edges (12, 12?) of the drainage body (11) to one another transversely to the longitudinal direction in a tension-resistant manner over the entire length of the drainage body. In order to allow the use of different covers (20) for different loads, for example while using the same drainage body (11), two types of engagement devices (13, 13?; 14, 14?) are provided on the drainage body.

Abstract: Coverings for structures which can be installed in the ground are known. In order to lock the covering on the structure, closures are known which comprise a snap bolt which is designed in such a way and is mounted movably on the covering (20) against the force of a spring device in such a way that, during closing of the covering (20), the snap bolt is forced back and snaps in behind a counterbearing (14, 14?) fixed to the structure in a closure position. To simplify the arrangement and also to improve durability, it is proposed that the snap bolt is mounted in a housing (40) which can be fastened in a housing receptacle of the covering (20).

Abstract: The invention relates to a support structure of a cover of a structure capable of being inserted into the ground, for example of a shaft or a channel, wherein the cover (10) comprises a traversable surface (11) and the support structure (20) extends downwards under said cover into the structure and comprises beam-shaped supports (21-23) such that their under support side (24) facing away from the surface (11) experiences a tensile stress when the surface (11) is loaded. The invention is further characterized in that between two areas (A, A?) a thickness (D) of the carriers with minimum tensile stress is configured substantially symmetrically in an increasing manner up to a maximum value and then, in turn, in a decreasing manner to form a ball shape when viewing the cover from below.

Abstract: Coverings for structures which can be installed in the ground are known. For example, these are drainage channels or manholes. In order to lock the covering on the structure, closures are known which comprise a snap bolt which is designed in such a way and is mounted movably on the covering (20) against the force of a spring device in such a way that, during closing of the covering (20), the snap bolt is forced back and snaps in behind a counterbearing (14, 14?) fixed to the structure in a closure position. To simplify the arrangement and also to improve durability, it is proposed that the snap bolt is mounted in a housing (40) which can be fastened in a housing receptacle of the covering (20).

Abstract: The aim of the invention is to allow a simultaneously stable and variable design of a drainage structure consisting of a drainage body (11) and a cover (20). This is achieved in that the drainage body (11) and the cover (20) continuously have engagement devices (13, 13?; 14, 14?; 23, 23?) when seen in a longitudinal direction of the drainage body (11), whereby the cover connects upper edges (12, 12?) of the drainage body (11) to one another transversely to the longitudinal direction in a tension-resistant manner over the entire length of the drainage body. In order to allow the use of different covers (20) for different loads for example while using the same drainage body (11), two types of engagement devices (13, 13?; 14, 14?) are provided on the drainage body.

Abstract: A drainage body is disclosed which comprises at least two substantially identically shaped surface units, that is a base unit and a substantially identically shaped top unit, which are combinable with one another in an installation spacing by way of spacers. It is proposed to form the surface units to be substantially interlockingly stackable in such a manner that the installation spacing of the surface units is considerably larger than their spacing in the stacked condition, whereby the spacers essentially have, for example, a frusto-conical or frusto-pyramid shape with a circumscribed cross-sectional area which becomes smaller as its distance from the surface units increases. As an alternative to this, it may be provided that the spacers are disposed in such a manner on the surface units that the base units and the top units are layable so as to be overlapping one another in the manner of a masonry bond. As a result this creates high stability with simultaneous space-saving storability and transportability.