Abstract: An improved bin is adapted to receive and store materials having fluid properties, such as liquids and granular materials. The bin is made of a fiberglass reinforced plastic material, and has a circular bottom arranged to rest on a foundation, and a cylindrical side wall bonded to a marginal portion of the bottom and extending upwardly therefrom. A cable has its lower end suitably anchored proximate the bottom, has its intermediate length helically wound around the outside of the side wall, and has its upper end suitably anchored proximate the top of the side wall. The improved bin also includes a plurality of vertical members, also formed of a fiberglass reinforced plastic material, spaced circumferentially around the inner surface of the side wall. Each vertical member defines with the side wall a sealed tubular cavity extending upwardly from the bottom.

Abstract: An expansible bottom structure for a fiberglass reinforced plastic tank allows a lower portion of the tank side wall structure to expand radially outwardly without significant deformation of its original shape.The improvement includes a fiberglass reinforced plastic batten having an upper portion bonded to the cylindrical side wall of a tank, a lower portion bonded to the bottom of the tank, and an intermediate arcuate transitional portion adapted to flex under tension to a less arcuate position. Such permissible flexure of the batten transitional portion enables the tank side wall structure to expand radially outwardly under hydrostatic load, while preserving substantially undeformed the desired shape and characteristics of the lower portion of the side wall structure. The batten provides the sole fluid-containing connection between the side wall structure and the tank bottom.

Abstract: An improved upstanding cylindrical tank is provided, in one aspect of the invention, with a ring-like stiffening member at its open upper end to resist flexure and deformation of the side wall structure under wind loading. The stiffening member has a cylindrical inner flange portion formed integrally with the tank wall, an annular web portion extending radially outward from an upper part of the upper flange portion, and a cylindrical outer flange portion depending from an outer part of the web portion and arranged concentrically with the inner flange portion. The stiffening member has a minimum vertical moment of inertia and is configured to have its vertical neutral axis located approximately midway between the furthermost fibers of the inner and outer flange portions.