Load-bearing structure comprising one vertical upright, provided with one longitudinal wall and one fastening opening made along the longitudinal wall; one fastening body, provided with one fastening wall and with one fastening portion made cantilevered on the fastening wall, insertable inside the fastening opening and movable in a sliding manner inside the latter between a fastening configuration, in which it is coupled to the fastening opening, by fastening the vertical upright to the fastening body, and one free configuration, in which it is uncoupled from the fastening opening, freeing the vertical upright from the fastening body. The fastening portion comprises a first fastening element, which extends along a first direction of extension (FDE), and a second fastening element, which extends along a second direction of extension substantially transverse to the FDE, the first and the second fastening element being adapted to fasten to the longitudinal wall in the fastening configuration.

A shelf assembly includes a left hand bracket and a right hand bracket, each with an upper shelf support and a lower shelf support. An upper shelf fits onto the upper shelf support and a lower shelf fits onto the lower shelf support.

A storage rack is provided. The storage rack includes a plurality of upright supports and a shelf support supported by each of the plurality of upright supports. The plurality of upright supports include a first upright support, a second upright support, a third upright support, and a fourth upright support each having an opening. The shelf support includes a shelf beam extending between the first and second upright supports. The shelf beam includes a body, a first tab, and a second tab. The first and second tabs each extend outwardly from an end of the body and are configured to engage the first upright support at opposing sides of the opening of the first upright support in order to detachably connect the shelf beam to the first upright support.

A concave square tube lifting storage shelf is provided. The concave square tube lifting storage shelf includes a plurality of post components, two fixed storage layers and a plurality of moveable storage layers. These post components each include a concave square tube, with each concave square tube comprising a concave plate. Each fixed storage layer includes a fixed shelf and a first assembly component, with the first assembly component being mounted on the fixed shelf. The first assembly component is fitted onto the outer side of the concave square tube, and the fixed storage layer is assembled between the post assemblies via the first assembly component. The movable storage layers each include a movable shelf and a second assembly component, with the second assembly component mounted on the movable shelf. The movable storage layers can move in the lifting direction.