To provide container-shaped members which improves strength by providing one or a plurality of hollow columns, floats or subsidizes the container-shaped members by filling materials of light and heavy specific gravities in a hollow column part, or improves strength and enhances high general purpose usability.

Container-shaped members 1 which are formed from hard synthetic resin box members composed of a circumferential part 2 and a bottom part 3, having the bottom, and open the upper surface so as to form an opening part 4, and the circumferential part 2 is formed into a tapered state gradually getting small towards the bottom face 3. Hollow column parts 5 which have the top end face closed or opened, are opened 5a in the center of the bottom face and project upward are integrally formed with the bottom part 3. This column part 5 can be filled with filler for increasing buoyancy or filler for increasing the strength. It is all right that a box part is provided in the outer circumference so that the box part is filled with the filler. These container- shaped members are connected vertically/laterally to each other so as to become a structure having water and gas permeabilities.