Abstract: A large semisubmersible building is made up of a submerged section installed underwater, an intermediate section consisting of a plurality of column structures erected on the submerged section at specified intervals, and an above-water section built upon the intermediate section so that it is always situated above water. The submerged section is made larger than the above-water section. Because of this construction, the large semisubmersible building remain stable and stationary at a specified depth of water even in stormy weather conditions. When the water level changes or when the specific gravity of the building changes as a result of changes in the weight of goods stored in the building, the semisubmersible building can be stably held at the specified depth of water.

Abstract: An underwater tunnel consisting of: a foundation body moored to the bottom of the water; a support frame erected on the foundation body; and a tunnel body formed integral with the support frame; wherein the tunnel body is formed in a two-layer construction which consists of an outer shell and an inner shell so that spaces formed inside the inner shell and between the outer and inner shells can be used for desired purposes, and the support frame is so formed that its vertical cross section is virtually a regular triangle and that a water tank is formed at the inside bottom of the support frame.

Abstract: A floating wave absorber is composed of a main wave-absorber body formed by a construction body floating on the surface of water, wires of which each one end is connected to an end portion of the main wave-absorber body, a first traction member of which one end is connected to the other bound end portion of each wire and the other end is fixed to an anchor, and a second traction member of which one end is connected to the bottom of the main wave-absorber body and fixed to another anchor. The main wave-absorber body is floated on the water according to a so-called "kite flying" principle and absorbs waves. Thus, the wave absorber is more advantageous in economic performance and free from washing-away by abnormally high waves in a typhoon, etc., and can be installed quickly and absorb waves effectively.

Abstract: An underwater building comprises a floating base that is to be fixed to a bottom under water or the sea and a building body is constructed on the base. The base floats on the water surface before construction of the body of the building, and the building body formed thereon has a double-walled construction having an opening between an outside wall and an inside wall. Water is selectively poured into and drained from the opening, and by its weight the building body is controllably sunk into the water. Only a gateway tower portion made in the upper portion of the building body is eventually left projecting out of the water.

Abstract: The flooring apparatus for pool or the like comprises an elevating floor formed almost identically with an opening area of a pool or the like, an elevator for moving the elevating floor vertically, and a means for holding the elevating floor at a desired level position, the elevating floor can be set securely and solidly at a desired level position on a small power by sealing the elevating floor hermetically with air for a buoyancy coming almost zero underwater, further one pool can be used for multiple purpose of adults' use, children's use, infants' use and others, thus providing a flooring apparatus for pool or the like which is simple in construction and moderate in cost.

Abstract: An improved floor-level adjusting device for a pool is particularly designed to be incorporated in an existing pool at low cost without the destruction thereof. The floor-level adjusting device for a pool has a movable floor disposed in a pool for vertical movement, and a plurality of lifting mechanisms disposed on and along the side walls of the pool and connected with the movable floor for moving the movable floor in the vertical direction so that the depth of water in the pool above the movable floor can be adjusted in an appropriate manner.

Abstract: An improved floor-level adjusting device for a pool is particularly designed to be incorporated in an existing pool at low cost without the destruction thereof. The floor-level adjusting device for a pool has a movable floor disposed in a pool for vertical movement, and a plurality of lifting mechanisms disposed on and along the side walls of the pool and connected with the movable floor for moving the movable floor in the vertical direction so that the depth of water in the pool above the movable floor can be adjusted in an appropriate manner.