Cavity Construction Patents (Class 405/55)
  • Patent number: 4976569
    Abstract: Subterranean cavities which can be filled with water or brine are also used for safely depositing ecologically harmful waste. In order to introduce the waste, which must not come in contact with the water or brine, a liquid which is not miscible with water and is specifically heavier than water or brine is let in below the water or brine, where it forms a layer, and the waste is introduced into this liquid via a pipeline, whereby the waste or the mixtures of waste and binding agents must be specifically heavier than the liquid. The displaced water or brine is upwardly removed.
    Type: Grant
    Filed: May 18, 1988
    Date of Patent: December 11, 1990
    Assignee: NUKEM GmbH
    Inventors: Georg Braehler, Benno Ganser, Paul-Gerhard Maurer
  • Patent number: 4958957
    Abstract: A system for the storage and dispensing of liquid product from an underground installation comprises a storage tank which bears on its top a containment chamber enclosing all fittings for apparatus which gasoline or other stored product will pass through under pressure. Attached to at least one fitting each are a fill means for introducing liquid to the storage tank, and pumping means for pumping fluid therefrom, both of which are entirely enclosed in secondary containment, the storage tank itself and piping also being enclosed in secondary containment, such that the system is pressure tight, and recovers all leaked fluid in a state in which the fluid can be reused.
    Type: Grant
    Filed: March 1, 1989
    Date of Patent: September 25, 1990
    Assignee: Sun Refining & Marketing Company
    Inventors: Robin Berg, Lawrence Mohns, Richard Oswald
  • Patent number: 4948296
    Abstract: A method of constructing a swimming pool by laying a concrete shell of 80 mm thickness without any substantial reinforcement. A glass reinforced plastic of 5 mm thickness is then laid over the concrete once the concrete has cured. This particular combination between the fiberglass and the concrete shell allows the shell to crack and move in relation to the reinforced plastic layer, without transmitting any stresses to the reinforced plastic layer. This results in a pool which allows any stresses due to soil subsidence, movement, etc. to be transmitted to the concrete shell and not the reinforced plastic layer thereby leaving the plastic layer free of cracks.
    Type: Grant
    Filed: December 18, 1987
    Date of Patent: August 14, 1990
    Assignee: Huntina Pty. Ltd.
    Inventor: Tom Salter
  • Patent number: 4934866
    Abstract: An underground storage tank installation apparatus and method for installing the same. The apparatus includes a fiberglass vault into which one or more underground storage tanks are secured and buried in a suitable excavation. Structural support members are formed within the walls of the fiberglass vault to provide adequate strength for the walls of the fiberglass vault so that the chances of cave-ins are minimized. Internal and external observation wells are provided, with automatic leak detectors, so that any leakage either inside or outside the fiberglass vault is automatically detectable. The preferred method for installing the fiberglass vault is to excavate a pit of predetermined dimensions and pour a concrete base in the bottom thereof. The sides of the pit are lined with sheetrock panels and a liquified fiberglass mixture is sprayed on to the panels and concrete slab, with vertical support members being secured to the sheetrock panels between subsequent layers of the fiberglass coating.
    Type: Grant
    Filed: March 10, 1989
    Date of Patent: June 19, 1990
    Assignee: Secondary Containment, Inc.
    Inventor: Donald G. Gage
  • Patent number: 4916937
    Abstract: A pressure barrier liner is an assembly of low permeability membranes disposed on above the other. A region is encapsulated between each adjacent pair of membranes. A pressurized fluid such as air or water is introduced into a selected group of the encapsulated regions to pressurize them to a selected pressure or pressures, thereby ensuring that any flow through the membranes or through disruptions in the membranes will be from within the pressurized regions to the regions outside the membranes which encapsulate the pressurized regions, rather than from the fluid storage region above the membranes, through the membranes and into the region beneath the membranes which is to be protected by the linear.
    Type: Grant
    Filed: May 18, 1987
    Date of Patent: April 17, 1990
    Assignee: Robertson Barrier Systems Corporation
    Inventors: Andrew M. Robertson, Walter Van Woudenberg
  • Patent number: 4890956
    Abstract: A rock chamber structure for containing gas or liquid under pressure is provided with a lining arrangement which transmits pressure of the contained gas or liquid to the surrounding rock while preventing build-up of external water pressure on the lining arrangement. A compressible drainage layer of loose granules is disposed between the rock and a concrete layer of the lining arrangement, and a thin metal sealing membrane is mounted to the concrete layer to seal the rock chamber. The concrete layer is anchored to the surrounding rock by expandible bolts which permit displacement of the concrete layer toward the rock. Pressure from the contained medium is transmitted to the surrounding rock through the metal liner, the concrete layer, and the drainage layer, while the drainage layer prevents the build-up of external water pressure.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: January 2, 1990
    Inventor: Torbjorn Hahn
  • Patent number: 4881849
    Abstract: A method for disposing of, confining, and isolating toxic waste material, which includes forming a plurality of housings underneath the surface of the earth. The housings are interconnected by a tunnel housing. At least one of the housings has a silo having a silo door that slidably opens and closes. The toxic waste is passed through the silo, through the silo housing and the tunnel housing, and into the other subterranean housing wherein the toxic waste is disposed. The silo door is then closed in order to enclose, confine, and isolate the toxic waste material.
    Type: Grant
    Filed: October 27, 1988
    Date of Patent: November 21, 1989
    Inventors: Harold C. Hoffine, John Forsythe, Leon Morgan
  • Patent number: 4875805
    Abstract: A toxic waste storage facility is formed of a plurality of contiguous storage cells. Each of the storage cells has walls made from compacted earth blocks and has a floor of compacted layers of clay with an impervious plastic liner beneath the layers of clay. A plurality of liquid storage containers, each containing toxic waste, are stacked in each of the storage cells. Clay filler is located within the walls of the storage cells and fills the space around the containers.
    Type: Grant
    Filed: September 6, 1988
    Date of Patent: October 24, 1989
    Inventor: Robert Gross
  • Patent number: 4842774
    Abstract: An improved waste disposal site for the above-ground disposal of low-level nuclear waste as disclosed herein. The disposal site is formed from at least three individual waste-containing tumuli, wherein each tumuli includes a central raised portion bordered by a sloping side portion. Two of the tumuli are constructed at ground level with adjoining side portions, and a third above-ground tumulus is constructed over the mutually adjoining side portions of the ground-level tumuli. Both the floor and the roof of each tumulus includes a layer of water-shedding material such as compacted clay, and the clay layer in the roofs of the two ground-level tumuli form the compacted clay layer of the floor of the third above-ground tumulus. Each tumulus further includes a shield wall, preferably formed from a solid array of low-level handleable nuclear wate packages.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: June 27, 1989
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Martin P. Golden
  • Patent number: 4818142
    Abstract: A method and apparatus are provided for forming a cementitious walled ground excavation outwardly of which ground settling is substantially eliminated. A form wall footing is initially erected and leveled upon the bottom of the excavation inward of the walls thereof and inner form walls are then erected upon the outer margin of the footing and anchored in position relative thereto after which an upstanding skeletal reinforcing rod frame is erected between the excavation and form walls and fluent cementitious material is poured about the skeletal framework between the excavation and form walls.
    Type: Grant
    Filed: November 13, 1987
    Date of Patent: April 4, 1989
    Inventor: James C. Cochran
  • Patent number: 4778628
    Abstract: Disclosed is an underground waste barrier structure that consists of waste material, a first container formed of activated carbonaceous material enclosing the waste material, a second container formed of zeolite enclosing the first container, and clay covering the second container. The underground waste barrier structure is constructed by forming a recessed area within the earth, lining the recessed area with a layer of clay, lining the clay with a layer of zeolite, lining the zeolite with a layer of activated carbonaceous material, placing the waste material within the lined recessed area, forming a ceiling over the waste material of a layer of activated carbonaceous material, a layer of zeolite, and a layer of clay, the layers in the ceiling cojoining with the respective layers forming the walls of the structure, and finally, covering the ceiling with earth.
    Type: Grant
    Filed: May 15, 1986
    Date of Patent: October 18, 1988
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Anuj J. Saha, David C. Grant
  • Patent number: 4717285
    Abstract: The invention concerns a cistern structure intended to be used as a subterranean cistern. The shell of the cistern has been formed of a material impermeable to the substance to be stored therein. The shell of the cistern has been encircled with mutually spaced annular juncture elements (13). The juncture elements (13) have been provided with anchoring elements (14) by the aid of which the cistern has been anchored in the rock or soil. The shell of the cistern is supported by a supporting layer in concrete construction, and the shell consists of sheet steel (12). The shell of the cistern is advantageously composed of element-designed components (11). The element-designed components (11) one upon the other have been joined to become a compound structure, with the aid of a juncture element (13). The juncture element (13) is advantageously a concrete ring cast on site.
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: January 5, 1988
    Assignee: Neste Oy
    Inventor: Jorma Pulkkinen
  • Patent number: 4708522
    Abstract: The present invention relates to a structure for storing radioactive material in rock, having a body (4) for accommodating radioactive material, the body (4) being encompassed by rock around which a cavity (3) may optionally be formed, there being arranged in the cavity a barrier (5) comprising a water-swelling elastoplastic material. The body (4) includes a substantially vertical central shaft (8), a vertical shaft (10) of annular cross-section and extending concentrically with the central shaft (8), and a plurality of vertical drifts (12) located at a distance from the center axis of the central shaft (8).
    Type: Grant
    Filed: November 25, 1985
    Date of Patent: November 24, 1987
    Assignee: Boliden Aktiebolag
    Inventors: Sten G. A. Bergman, K. Ivar Sagefors, Bengt A. Akesson
  • Patent number: 4708523
    Abstract: A rock cavity for storing fluids, solid products for some other purpose, such as the protected manufacture or production of goods, comprising a substantially vertical, cylindrical rock cavity comprising a conical top section (14), and a conical or horizontal bottom section (15) and a vertical section (1) extending therebetween and presenting in cross-section a polygonal shape, wherewith vertical shafts (11) are located in at least half the corners of the polygon.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: November 24, 1987
    Assignee: Boliden Aktiebolag
    Inventors: Karl I. Sagefors, Per G. Persson
  • Patent number: 4671700
    Abstract: The walls of the cavity (10) are interconnected by rounded portions. The cavity (10) may be cylindrical in shape with hemispherical ends (11, 12). This shape reduces cracking in the walls during an initial cavity cooling process.
    Type: Grant
    Filed: February 4, 1986
    Date of Patent: June 9, 1987
    Assignees: Societe Francaise de Stockage Geologique, Geostock and Distrigaz
    Inventors: Alain Boulanger, Walter Luyten
  • Patent number: 4639164
    Abstract: Sumps are mounted on manway fittings of underground tanks, and all piping runs are routed through a sump. Underground portions of pipes between a sump and a point above ground are provided with a double wall. Filling spills and leakage from pipes into the environment are thereby generally prevented.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: January 27, 1987
    Assignee: Owens-Corning Fiberglas Corporation
    Inventors: Peter J. Pugnale, Michael J. Messmer
  • Patent number: 4625680
    Abstract: A low cost apparatus for the storage of fluent materials below ground. The apparatus comprises a bore hole in the ground, a collar substantially covering the bore hole and a liner disposed within the bore hole adapted to contain the fluent material against contamination or seepage.
    Type: Grant
    Filed: July 20, 1984
    Date of Patent: December 2, 1986
    Inventor: Lawrence J. Hogan
  • Patent number: 4596490
    Abstract: This invention relates to a new and novel method for the underground storage of fluid materials including those which are readily soluable or reactive with water or brine such as concentrated caustic soda, ethylene dichloride or anhydrous ammonia within chambers developed in salt formations via solution mining and from which essentially all the brine has been removed; and the chambers thereby produced. More particularly this invention relates to methods for making underground storage chambers; of recovering the brine formed in the making of the chamber; isolating the contaminants, i.e., the insolubles mixed with brine resulting from the solution mining of the storage chamber, such that fluids soluable or reactive with water or brine can be stored therein; and also to a method for controlling the velocity of free fall of materials injected into the chamber for storage, such that erosion of the equipment employed is minimized.
    Type: Grant
    Filed: March 15, 1984
    Date of Patent: June 24, 1986
    Assignee: Texas Brine Corporation
    Inventors: Neal E. Van Fossan, John Rutherford
  • Patent number: 4586849
    Abstract: Radioactive waste material is permanently stored without the need of constant surveillance by depositing the material in a cavity located in a rock formation above the water table and between two layers of water impervious rock. Preferably the entrance to the cavity is located in a mountainside or bluff in a layer between the two water impervious layers, which layer is more easily penetrable than the two water impervious layers. The cavity may include a passage which is reinforced with a reinforcement material such as concrete and is surrounded by a plurality of boreholes to aid in dissipating the heat of decay.
    Type: Grant
    Filed: December 1, 1983
    Date of Patent: May 6, 1986
    Assignee: Nuclear Protection Systems, Inc.
    Inventor: Richard P. Hastings
  • Patent number: 4572707
    Abstract: The present invention relates to a method in the excavation of rock caverns, substantially cylindrical vertical caverns, for storing liquids or dry products, or for use in storing process units, in which method an upper and a lower circumferentially extending cavern (4, 11) is formed, the caverns (4, 11) having an outer diameter which is greater than the diameter of the ultimate rock cavern (1); in which the caverns (4, 11) are connected together by means of vertical holes (12) drilled in the region immediately outside the ultimate rock cavern (1), these vertical holes (12) serving to drain water from the aforementioned region, for the purpose of minimizing the extent to which water can penetrate the rock cavern (1). (FIG. 1).
    Type: Grant
    Filed: July 24, 1984
    Date of Patent: February 25, 1986
    Assignee: Boliden Aktiebolag
    Inventor: Ivar K. Sagefors
  • Patent number: 4488834
    Abstract: A method for developing, evacuating, using, sealing, and re-entering multiple stacked cavities which are created from a single well in salt deposits. The cavities are created in a salt deposit by circulating raw water through concentric casing strings in the well. Each of the cavities is evacuated of liquids prior to use. After storage material is injected into a cavity, the cavity is sealed by setting a plug in the well bore above the top of the cavity. The cavities may be re-entered by drilling out the plug or by drilling a directional well directly into the cavity.
    Type: Grant
    Filed: November 17, 1982
    Date of Patent: December 18, 1984
    Assignee: Empak, Inc.
    Inventors: Mark W. Hooper, Edward J. Voorhees
  • Patent number: 4474506
    Abstract: Method for constructing a liquid-product storage location in rock formations, said location comprising a first cavity, and a plurality of second cavities located outside the first cavity. In accordance with this method there is first formed a tunnel (7) which slopes from the surface of the ground down to a given point in the rock formation. There is then blasted from said given point a second sloping tunnel (22) which meanders in the ultimate storage location in a plurality of turns down to the level of the bottom (11) of the ultimate first cavity. Horizontal primary tunnels (T1-T6) are then blasted from the meandering tunnel at a plurality of levels.
    Type: Grant
    Filed: April 7, 1983
    Date of Patent: October 2, 1984
    Assignee: Boliden Aktiebolag
    Inventor: Ivar K. Sagefors
  • Patent number: 4462714
    Abstract: The invention disclosed herein is a method and apparatus for setting a cement plug in the wide-mouth shaft of an earth cavern. The apparatus includes a deflated balloon with a liquid fill pipe therein. In practice, the cavern is first filled with a liquid. Following this, the balloon is encased in a releasable girdle and lowered into the cavern through a casing, along with a cement fill pipe which remains above the balloon. When the balloon reaches a certain point in the cavern, below the casing, the girdle is released from the balloon and the balloon is filled with a liquid to inflate it. The inflated balloon seats against the cavern walls to provide an excellent support for the cement, which is pumped down the cement fill pipe.
    Type: Grant
    Filed: April 4, 1983
    Date of Patent: July 31, 1984
    Assignee: The Dow Chemical Company
    Inventors: Charles F. Smith, George R. Parks, Gustavo A. Correa, Ralph N. Holley
  • Patent number: 4454721
    Abstract: A constant-pressure air-storage cavern wherein the floor and the roof of the cavern are inclined at an acute angle with respect to the horizontal and the transition portion from the cavern into the air riser and into the water tunnel is expanded to form a dome and a sump, respectively. In the sump a vortex generator is provided.
    Type: Grant
    Filed: September 13, 1982
    Date of Patent: June 19, 1984
    Assignee: BBC Brown, Boveri & Company, Limited
    Inventors: Reinhard Hurlimann, Paul Zaugg
  • Patent number: 4431341
    Abstract: A procedure for constructing a concrete lined underground chamber along a bore hole drilled within the earth. Such chambers serve as access work chambers for carrying out other various drilling and mining operations, such as, for example, horizontal drilling operations for steam enhanced recovery of oil. In constructing the lined chamber, the bore hole is initially drilled in the earth to a predetermined depth at which the chamber is to be constructed. In a first belling operation, a first bell-shaped chamber is formed. A substantial portion of the floor of this first chamber is then covered with a mound of gravel material. The remainder of the first chamber is then filled with concrete. Subsequently the bore hole is redrilled to a depth extending below the bottom of the first chamber and a second belling operation is carried out for forming a second bell-shaped chamber.
    Type: Grant
    Filed: April 27, 1982
    Date of Patent: February 14, 1984
    Assignee: Santa Fe International Corporation
    Inventor: Hans Nilberg
  • Patent number: 4363563
    Abstract: A system for the underground storage of fluids, e.g. petroleum products in rock. The system comprises a plurality of cavities excavated in the rock. Each of said cavities has a cylindrical shape with a circular or oval cross-section. Each cavity forms a storage space the walls of which are formed by the rock and directly absorb the pressure of the fluid stored in the cavity. The cavities are arranged with their center axes standing vertically, and the vertical height of each cavity is greater than or equal to the diameter of its cross-section. The distance from each cavity to adjacent cavities is equal to or greater than the diameter of the cross-section of the cavity, and the centers of the cross-sections of the cavities as seen in a horizontal cross-section of the whole system are positioned in a two-dimensional pattern.
    Type: Grant
    Filed: February 21, 1979
    Date of Patent: December 14, 1982
    Assignee: WP-System Aktiebolag
    Inventors: Tore J. Hallenius, Karl I. Sagefors
  • Patent number: 4343569
    Abstract: An apparatus for preventing the blowing out of the water supply of constant pressure air storage installations for gas turbine power plants, which is intended to be installed as a preferably prefabricated unit at the upper end of a riser tube or pipe of an air storage cavern. The apparatus contains venting tubes, the lower ends of which are staggered in elevation. Further, there are provided guide elements which, on the one hand, guide part of the water-air mixture flowing out of the riser tube into the vent tubes or pipes and, on the other hand, form an extended flow channel for the remaining water-air mixture which directly flows into a compensation basin.
    Type: Grant
    Filed: September 30, 1980
    Date of Patent: August 10, 1982
    Assignee: BBC Brown Boveri & Co. Ltd.,
    Inventor: Alfred Schwarzenbach
  • Patent number: 4326818
    Abstract: Water is stored in a sub-surface reservoir that has flexible walls of grouted in situ soils. The water is stored in the voids between soil particles within the reservoir. Usable voids within the container vary from about 20% to about 40% of the totally enclosed volume of the reservoir. The bottom of the reservoir is a natural impervious sub-strata. No excavating of soil is required as they are, generally, sand and gravel deposits that overlie impervious aquicludes. A grout pipe is inserted into the ground by any conventional method, and then grout is continuously injected through the pipe under pressure as the grout pipe is being withdrawn, thus forcing the grout into adjacent soils. Selective positioning of successive grout pipes leads to the formation of a wall.
    Type: Grant
    Filed: January 29, 1980
    Date of Patent: April 27, 1982
    Inventor: Dudley L. Willis
  • Patent number: 4239416
    Abstract: A cavity in the earth such as a reservoir, tunnel or the like is lined with a flexible, fluid impervious sheet such as a rubberized fabric supported by a grid-like skeleton structure having distorted elongated resilient structural members which are under tension and press the liner against the walls of the cavity. The members of the skeleton structure are made of a material which resists permanent distortion. The liner is disposed between the skeleton structures and the wall of the cavity and is fastened at spaced points to the wall of the cavity.
    Type: Grant
    Filed: September 15, 1978
    Date of Patent: December 16, 1980
    Assignee: Pirelli Furlanis Applicazioni Indrauliche
    Inventors: Bruno Borca, Emilio Ruscelli
  • Patent number: 4230368
    Abstract: A method for elevating extremely large blocks of earth by displacement with a slurry composed of water and locally excavated materials. The blocks are separated on lateral faces by variously drilling, jetting, fracturing, and kerf cutting operations. The blocks are separated at the lower end by notching and hydraulic fracturing. Block movement is started by injecting gelled fluid into the narrow separations.In one set of applications the high density slurry filling the side clearances is less dense than the block being elevated. In these cases the earth blocks are displaced upward by injecting fluid into the underside, and the non hydrostatic component of the displacement pressure is contained by the gel strength of the slurry filling the narrow side clearance. In a second set of applications the blocks being elevated contain a high percentage of coal, and slurry filling the side clearances exceeds the block density. The blocks are then displaced upward by hydrostatic pressure.
    Type: Grant
    Filed: February 12, 1979
    Date of Patent: October 28, 1980
    Inventor: James M. Cleary, Jr.
  • Patent number: 4200336
    Abstract: An in situ oil shale retort is formed in a subterranean formation containing oil shale. The retort contains a fragmented permeable mass of formation particles containing oil shale. During retorting, oxygen-supplying gas is introduced into an upper level of the fragmented mass for establishing a combustion zone and for advancing the combustion zone downwardly through the fragmented mass. Liquid and gaseous products, including shale oil and off gas, are withdrawn from a generally U-shaped production level drift at a lower level of the fragmented mass. Liquid in a lower portion of the U seals against the roof of the drift to provide a gas seal which inhibits passage of off gas from a first leg of the drift in communication with the retort to a second leg of the drift remote from the retort. A retaining wall in the second leg of the drift can provide lateral support for the liquid forming the gas seal, and help minimize the depth of excavation of the U-shaped drift.
    Type: Grant
    Filed: July 17, 1978
    Date of Patent: April 29, 1980
    Assignee: Occidental Oil Shale, Inc.
    Inventor: Robert S. Burton, III
  • Patent number: 4166709
    Abstract: Hazardous chemical waste materials can be vaulted for permanent disposal by encapsulation in a water-impermeable film and a soil cement.
    Type: Grant
    Filed: August 3, 1978
    Date of Patent: September 4, 1979
    Assignee: Stabatrol Corporation
    Inventor: Richard E. Valiga
  • Patent number: 4165945
    Abstract: A method for storing fluid underground at maximum pressure p, comprising the steps of digging, at a depth at which the lithostatic pressure generated by the weight of the abovejacent soil formations is at least p, an underground cavity in which is made a tight deformable casing anchored to the cavity wall at some places only, while it can freely expand or contract in every direction between said anchoring places, then of injecting pressured fluid into said casing in order that the latter be fully applied against the cavity wall, the possible movements of which said casing subsequently follows by gliding, the pressure of said fluid being, at every moment, counterbalanced by the lithostatic pressure of the cavity walls transmitted to said fluid by the thus expanded casing.
    Type: Grant
    Filed: November 29, 1977
    Date of Patent: August 28, 1979
    Assignees: Commissariat a l'Energie Atomique, Societe Nationale Elf Aquitaine
    Inventors: Jacques Despois, Francis Nougarede
  • Patent number: 4136493
    Abstract: Liquefied gas is stored in a large rigid or semirigid cylindrical container. Between the walls and floor of this container and the walls and floor of an outer container, which may be an earthen cavity in which the container rests, is distributed a continuous layer of insulating material such as perlite or vermiculite in granular form. This insulating material serves as the sole means of support for the rigid or semirigid container and the liquefied gas stored therein. An impediment is included in the construction near the intersection of the floor and side wall of the rigid or semirigid container, the impediment completely encircling the container to substantially limit the cross-sectional area through which the granular insulation material may flow upward. By confining this cross-sectional area, the creep or migration of insulation material from beneath the container during initial filling, repeated filling and emptying of the liquefied gas contents of said container is substantially reduced or eliminated.
    Type: Grant
    Filed: September 20, 1976
    Date of Patent: January 30, 1979
    Assignee: NRG Incorporated
    Inventors: Rolland H. Bradford, Paul V. Laylander, Anthony J. Baranyi
  • Patent number: 4112690
    Abstract: Subjacent and lateral supporting soil for an underground tank is stabilized wherein a tank embedded therein is secured against flotation irrespective of the water table level of the surrounding soil. The lateral supporting soil is encased within a well and the subjacent soil is hardened to minimize seepage of water into the soil adjacent to the tank. Means are also provided to remove excess water from the confines of the well thereby minimizing flotation pressure on the tank.
    Type: Grant
    Filed: November 15, 1976
    Date of Patent: September 12, 1978
    Assignee: Kajima Kensetsu Kabushiki Kaisha
    Inventors: Kazuo Hosoya, Munetaka Kubota