Abstract: A structure such as a rack comprises columns connected together by beams, positioned in transverse relation to the columns. The rack is provided for use in warehouses or elsewhere. For example, pallets may be placed across pairs of beams for storage in the rack. By this invention, means are provided for retaining the beams and columns in a range of positions of registry in which first apertures in the columns and second apertures in the beams overlap in offset relation. Bolts extend through the overlapping first and second apertures, with the first and second apertures being each of larger diameter than the bolt means. The distance of overlap between the first and second apertures should be typically less than the diameter of the bolts. As a result of this, the beams and columns can be tightly affixed together by the bolts despite unpredictable positional variations in the beams and columns as they are so affixed.