Abstract: The disclosure is related to a method for forming structures in a liquid, preferably underwater using a flowing, settable material, wherein the material used has a density which is substantially equal to the density of the liquid in which the structure is formed as well as a system for such method and structures formed.

Abstract: Method of constructing a vault of a large storage tank for liquefied natural gas by first modeling the vault with a 3-D modeling software application, then partially building the vault with a framework and a first set of covering panels fixed on the framework where the panels do not touch each other, but leave a number of gaps between them, measuring the dimensions of the actual gaps between the panels using a 3-D scanner, producing a second set of panels according to the scanned dimensional data, and finally filled the gaps between the first set of panels with the second set of panels, which are much smaller than the first set of panels, making the building process earlier and more accurate, which are difficult issues in building large tanks for liquefied natural gas.

Abstract: The present disclosure discloses an air-borne multilayer film building structure which includes an independent film, a heat-insulation structure covering the independent film, and an airbag cover covering or an outer film cover covering the heat-insulation structure. The heat-insulation structure is installed on the outer wall of the independent film and includes at least two heat-insulation layers sequentially from inside to outside. Each heat-insulation layer is formed by paving a plurality of heat-insulation panels, the heat-insulation panels in every two adjacent heat-insulation layers being installed in a staggered manner. The outer heat-insulation layer covers a seam of the inner heat-insulation layer thereof. The air-borne multilayer film building structure has the advantages of good heat-insulation property, good airtightness, convenience in construction and the like.

Abstract: This invention relates to a self-supporting three-dimensional prestressed structure, as well as a method and a device for erecting same, to be employed in the construction of residential and nonresidential buildings. The structure is constructed of vertical form-defining flexible rodlike members (1) stressed during the construction of the structure, as well as horizontal flexible rodlike members (2) each forming a closed curve. The horizontal members (2) are also stressed during construction and welded or rigidly affixed by other means to the vertical form-defining members (1). Instead of horizontal circular members (2) the structure can be constructed completely or to some extent using a spiral member, also stressed during the construction of the structure that is rigidly affixed to the vertical form-defining flexible members (1).

Abstract: Method of fabricating a 3-dimensional structure, mesh formwork element for fabricating a 3-dimensional structure, and method of fabricating the same. The method of fabricating a 3-dimensional structure comprises providing a mesh formwork element such that a cavity bound by at least two opposing portions of the mesh formwork is formed; accumulating a material in the cavity; and allowing the material to harden; wherein apertures in the at least two opposing portions of the mesh formwork element are adapted to the hydro-static pressure of the accumulated material or vice versa such that at least two surfaces of the hardened material substantially take on the respective shapes defined by the two opposing portions of the mesh formwork element.

Abstract: A system for creating a cementitious building includes a support structure comprising a plurality of support members, and an inflatable rigidizable structural (IRS) form. The IRS form comprises a plurality of geosynthetic cementitious composite mat (GCCM) sections having GCCM configured to absorb water and rigidize in response to hydration, each GCCM section being coupled to another GCCM section of the plurality such that the IRS form is pneumatically inflatable.

Abstract: A modular geodesic dome construction simultaneously optimizes vertex positioning to be equidistant from a central point and minimizes a number of uniquely shaped triangular panels utilized in construction. The dome construction includes a plurality of triangular panels being coupled together along sides of the triangular panels forming a geodesic polyhedron structure. Each side of each of the triangular panels has a length corresponding to an associated one of only five length factors times a radius of the geodesic polyhedron structure. Additionally, the five distinct shapes of the triangular panels are either isosceles or equilateral triangles.

Abstract: A new inner passageway through a pre-cast concrete structure damaged by corrosion may be formed by stackable inserts formed of polymer concrete. The inserts may be stacked in the old passageway through the pre-cast concrete structure such that an inner surface of the stacked inserts forms a new passageway through the pre-cast concrete structure. A grout may be poured between an outer surface of the stacked inserts and an inner surface of the pre-cast concrete structure forming the old passageway. The surfaces of the stackable inserts may have superior resistance to corrosive acids such that the need for future repair is greatly reduced. Suitable pre-cast concrete structures for rehabilitation include pre-cast concrete structures utilized in wastewater systems, including manholes and other similar structures. In this manner, the damaged pre-cast concrete structures do not need to be removed during the rehabilitation.

Abstract: In one illustrative embodiment of a coated feeder, a coating is integrated into the structural components of the feeder. The coated feeder may include a base, ridge, and back, which may all be integrally formed with one another. The coating may include an exterior surface opposite concrete. The surface of the coating adjacent the concrete may include at least one tab, at least one linear protrusion, at least one hook, and at least one channel.

Abstract: In exemplary implementations of this invention, a nozzle sprays foam, layer by layer, to fabricate a fabricated object according to a CAD model, and a subtractive fabrication tool removes material from the fabricated object according to a CAD model. The fabricated object comprises a mold or an interior form. The foam may be low-density, high strength and fast-curing. The foam may be used for large-scale 3D printing. For example, the foam may be used to 3D print molds for walls of homes. The foam molds may be left in place, after casting concrete in the molds, to serve as insulation. Or for example, the foam may be used to 3D print on site an internal form for a large wind turbine blade. The wind turbine blade may then be produced on site by depositing fiberglass on the outside of the internal form.

Abstract: An assembly and method of constructing a concrete tower is provided. The method includes steps of erecting a central pillar, mounting a platform on the central pillar, setting a slipform defining a portion of the concrete tower, pouring liquid concrete from the platform into the slipform, and leaving the liquid concrete to solidify in the slipform. The slipforming repeats to form further portions of the concrete tower. Each of the further portions of the concrete tower is formed on top of a preceding one of the portions of the concrete tower. The assembly includes a central pillar, at least one slipform and a platform mountable on the central pillar and comprising means for pouring liquid concrete into the at least one slipform.

Abstract: An assemblage which form a beveled edge in a slab-on-grade foundation trench. The device is comprised of straight members corner members, and a connector member to hold the larger members together, an angle brace to maintain the proper bevel angle of 45° degrees, and a stake to anchor the device to the ground. When the device is assembled it forms a box-like structure whose sides and corners are sloped inwards at a 45° degree angle. The device simply needs to be positioned within the perimeter form, and filled with dirt from digging the trench; in order for the device to properly function as a device designed to make foundations much stronger.

Abstract: The invention concerns a processing apparatus for processing an upper segment edge of a pylon segment of a concrete pylon for preparing the pylon segment for placement thereon of at least one further pylon segment. According to the invention it is proposed that the processing apparatus includes a processing means for processing the segment edge, and a carrier apparatus to be fixed in the region of the segment edge for displaceably carrying and guiding the processing means along the segment edge.

Abstract: A wind turbine tower is made of reinforced concrete with fibre rovings as reinforcements, wherein the fibre rovings are basalt fibre rovings. In one embodiment, the basalt fibre rovings may include, for example, a bundle of multiple parallel oriented basalt fibers forming a thin rope.

Abstract: An apparatus and method for constructing a cryogenic storage tank (700) having a welded inner tank (702), an outer shell (704) surrounding the welded inner tank (702), a concrete foundation (728) comprising a raised portion (752), a plurality of cellular glass blocks (734) positioned directly on top of the raised portion (752) of the concrete foundation (728), a leveling course of concrete (736) poured on top of the uppermost layer of the plurality of cellular glass blocks (734), and a mounting apparatus (718) affixed to the concrete foundation (728), where the welded inner tank (702) is positioned on top of the leveling course of concrete (736) and the outer shell (704) is affixed to the mounting apparatus (718) at locations around the periphery of the outer shell (704).

Abstract: Detectable warning areas (DWAs) and methods of forming the same are provided. A mat template having one or more holes can be placed over a substrate, and a dome-forming material can be filled in the mat template by pouring the dome-forming material over the mat template and working the dome-forming material into the one or more holes of the mat template. The mat template can remain in place until the dome-forming material is completely cured, and then the mat template can be removed. DWAs formed according to this method display improved properties, including increased bond strength.

Abstract: An apparatus is disclosed for rotating a structural profile quickly and easily on a single spindle drill line without the use of a crane. The apparatus has two arms which can lay flat or create any angle less than 180 degrees between the two. The apparatus can move horizontally along the drill line and can lift the structural profile vertically for movement and during rotation. This will allow a drill machine operator to rotate large and heavy structural profiles on a drill line and position them with the datum blocks in order to drill the different sides without the need for an overhead crane or other lifting device and without any additional labor to assist with manual flipping and positioning.

Abstract: A new procedure for constructing cryogenic storage tanks involves erecting a freestanding metal liner. The liner is sized and configured to withstand the hydraulic forces the concrete wall of the tank being poured without the need for temporary stiffeners on the inside surface of lower portions of the liner. Lateral tension ties can be connected to anchor ties on an outward surface of the liner and used to tie the liner to outer formwork. These ties may be spaced up to about 2 m apart. Studs can also be provided on the outer surface of the liner, and a cylindrical ring of cryogenic steel can be integrated into the liner.

Abstract: A process of forming a concrete column using a concrete column forming tube lined with a flexible and compressible elastomer sleeve having a randomly dispersed rigid granular material encapsulated therein to form a concrete column having a textured surface. The flexible and compressible elastomer sleeve is formed by mixing a liquid elastomer with a rigid granular material and applying the mixture over a textured generally cylindrical form and curing the liquid elastomer. A colorant may be applied to the inside surface of the flexible and compressible elastomer sleeve to form a concrete column having a colored and textured surface.

Abstract: A tie system and method for forming a wall from a hardenable building material. In one embodiment, the tie system includes multiple ties configured to be directly interconnected into a vertically extending tie stack such that multiple tie stacks can be positioned over a footing in a spaced apart arrangement. The multiple tie stacks are configured to extend substantially perpendicular between substantially parallel panel structures. Each tie stack includes one or more base members and one or more wall ties, each of which directly attach to each other in a vertically stacked arrangement.

Abstract: An apparatus and method is provided for lining the wall of a manhole. The apparatus may include a liner assembly, which includes an expansion device, an auxiliary bladder, a primary bladder, and a liner. The auxiliary bladder is first inflated near the top of the manhole. Next the primary bladder may be expanded to press the liner against the wall of the manhole. The liner, being impregnated with a resinous material, is pressed against the wall until the resinous material cures and hardens. The expansion device, auxiliary bladder, and primary bladder are then removed from the manhole. The result is a repaired manhole wall.

Abstract: An emergency shelter includes a domed foam structure that is constructed on-site or at a remote location from foam that can be mixed on-site. The structure can be made on-site by spraying foam in a flowable state in a predetermined pattern to build up walls to form a dome. The foam can be sprayed, for example, in a substantially helical pattern from a centrally located spray nozzle that is rotated to deposit a finite-thickness increment of foam over a time period sufficient that, by the time the nozzle reaches a previously sprayed area, the foam already deposited has had time to cure.

Abstract: A concrete formwork tube, said tube including: an internal lining; an external lining; and two or more complementary mould segments, adapted to be received between said external and internal lining; each mould segment having an inner face and an outer face; said mould segments, when assembled and substantially restrained by the external lining from relative movement, defining a moulding cavity open towards an upper and a lower end of the formwork; and at least one locking segment, said locking segment adapted to be disposed between two of said mould segments, thereby to tighten the fit of the assembled mould segments inside the external lining.

Abstract: A post sleeve provides a substantially permanent base for supporting a post for a fence or sign, and from which one post can be removed and replaced with another post. The sleeve includes a concrete body that is poured on site, using a sleeve core prepositioned in the post hole, and around which wet concrete is poured. After the concrete is cured, the core is removed, leaving a post sleeve cavity configured to receive a post. The core can be rigid, or can include a flexible shell and stiffener. A preformed post sleeve top can be attached to the sleeve core and positioned therewith in the post hole, to become a permanent part of the post sleeve, once the concrete cures. A drain is attached to the core, and remains in the sleeve when the core is removed, and can be a percolation chamber, or passage extending below the sleeve.

Abstract: The present disclosure provides a method for producing detectable warnings (16) on substrate surfaces (14), which includes providing a mat (30) with a top surface (38) and a bottom surface (36) and a pattern of mat through holes (34) extending through the mat (30). The through holes (34) comprise a lower portion (44) defining a lower mat opening (33) and an upper portion (32) defining an upper mat opening (35), wherein the upper mat opening (35) is larger in transverse dimension than the lower mat opening (33). The method further includes placing the mat (30) on a substrate surface (14), wherein the bottom surface (36) of the mat (30) is adjacent the substrate surface (14), and injecting into the mat through holes (34) a viscous substance (40) having the ability to cure into a solid. The method further includes removing the mat (30) at the appropriate time to form raised detectable warnings (16) on the substrate surface (14).

Abstract: Apparatus and methods for multi-piece tubing are disclosed. Optional nestable embodiments (12, 14, 16, and 18) provide benefits in storage, transportation, and use. Optional interlocking elements (30, 32) provide benefits in ease of assembly and use, and possible disassembly, including with other tubing or non-tubing elements such as a base (20). End cover elements (19) can protect tube's interior from undesired dirt, liquid, or other contaminants, and can be removable. Methods include use in forming concrete pier footings or other building supports.

Abstract: A method and apparatus for constructing a snow shelter are disclosed. A slip form allows snow or ice crystals to be compacted in situ in large continuous blocks. Each block is built upon the previous as the slip form is rotated incrementally around a generally horizontal axis (175). The slip form is a convex shape. The convex shape, or profile, is tailored to the size and shape of the shelter desired. The resulting shape of the snow shelter is a surface of revolution of the profile of the slip form around a horizontal axis. Variations of the shelter's shape are explained herein. Various embodiments are described herein. Some of the advantages of the embodiments include: faster and more efficient construction, simple operation, and tailored size and shape of the finished shelter.

Abstract: Methods and equipment for forming beveled edge(s) around the core opening in a concrete block are disclosed. The formation of the beveled edge(s) minimizes feathering along the block edges that are beveled as the block is stripped from a mold. Any feathering that does occur is shifted away from the bottom surface of the block to allow the block to lay flat on other blocks when dry stacked in a wall.

Abstract: A multi-sectional form includes first and second half-cylindrical sections with each section having opposed edges. The cylindrical sections are secured together by two elongated generally H-shaped connectors, each connector including a pair of opposed generally U-shaped grooves. The first and second cylindrical sections are connected together by inserting one edge of one section and one edge of another section into the opposed U-shaped grooves of one H-shaped connector. One or more bands are secured around the exterior of the sections to secure and hold the sections together.

Abstract: Disclosed are a structure of an intermediate wall of a three arch excavated tunnel, which effectively exhausts subterranean water from a peripheral ground, and a method for constructing the tunnel. The method comprising the steps of: (a) excavating an upper portion of a central tunnel 10; (b) excavating a lower portion of the central tunnel 10; (c) forming an intermediate wall 20 and grouting a gap formed in the intermediate wall 20; (d) excavating an upper portion of a left main tunnel 30; (e) excavating an upper portion of a right main tunnel 40; (f) excavating a lower portion of the left main tunnel 30; (g) excavating a lower portion of the right main tunnel 40; and (h) installing a drain board 50 and a waterproof layer 60 and casting lining concrete 70 therein so that the tunnel is easily drained through drain pipes 65 and residual water pressure is eliminated.

Abstract: Methods and apparatus for fabricating structures, extrusion units, and structures fabricated using such methods and apparatus are disclosed. The apparatus may include a support configured for rotation about a central axis, a carriage that may move along the support when the support rotates about the central axis such that the carriage may move along a first spiral path about the central axis, and an extrusion unit that may be supported by the carriage and may move along a second spiral path as the carriage moves along the first spiral path. The extrusion units may be configured to extrude a strip of material through an extrusion die as the extrusion unit moves along a previously extruded strip of material such that the extruded strip may be fused onto the previously extruded strip as the extruded and previously extruded strips pass the extrusion die.

Abstract: Device for producing an elongated concrete element extending in the vertical direction, for example a tower of a wind turbine generator system, comprising an inner casing and an outer casing, the inner casing and the outer casing being configured in such a way that between the inner casing and the outer casing there is an interspace, which is of a height that is less than the height of the concrete element to be produced. A number of pumps are used, in order to pump concrete into the interspace. The pumps are designed in such a way that the concrete can be introduced at high pressure in such a way that the interspace is filled with concrete and that the concrete element is forced vertically upwards out of the interspace during the hardening of the concrete. As the concrete element rises, an attachments, that later serves for pulling up and mounting various elements, is transported upwards.

Abstract: This invention relates to a reinforcement structure which is used in providing cementitious mixtures supplemental support and strength upon setting, and more particularly, to a reinforcement structure which comprises a plurality of oriented reinforcing fibrous and/or filamentary components having a finite cut length, and fastening the reinforcing fibrous and/or filamentary components by one or more circumferential retaining elements.

Abstract: A hybrid arched overfilled structure includes a combination of pre-cast side elements and at least one cast-in-place crown sector element. The side elements are pre-cast generally in a horizontal orientation and subsequently lifted into place. The crown sector element is cast in place between the side elements. In one form of the invention, each of the three sections makes up about one-third of the overall arch span.

Abstract: A metallic receptacle is embedded in the concrete material of a burial vault. The receptacle contains archival quality paper that records information identifying the person interred in the burial vault and the precise location at which the vault was buried. The receptacle is sealed by a cap that may be removed to access the archival information without opening the vault.

Abstract: A monolithic dome shaped building of a size suitable to receive at least one relatively large vehicle, such as an airplane, is formed with a generally rectangular shaped access opening of sufficient size to enable passage of an airplane or other large vehicle into and out of the building. A three-dimensional unitary door is supported at an upper marginal edge on a guide track for lateral movement of the door between a first position closing the access opening and a second open position enabling passage through the access opening. The door includes a rigid frame structure having spaced upstanding frame members having outer convex surfaces similar to the convex contour of the dome wall adjacent the access opening.

Abstract: A method for repairing in-ground tunnel structure involves applying a first curable resin over a cementitious liner which lines the interior wall surfaces of the tunnel, drilling drainage holes in the cementitious liner, and filling the drainage holes with a second curable resin. The resins are allowed to cure and harden. The cured resins seal the wall surfaces and drainage holes to provide a composite tunnel structure having high mechanical strength and resistance to fluid leaks.

Abstract: Method and apparatus suited for forming retrofit detectable warning surfaces on existing surfaces or new warning surfaces. Apparatus includes a tool in the form of a stamp having one or more dome-shaped volumes that may be truncated domes. Dome-shaped volumes may have interior beginning on a bottom side of a stamp and the truncated portion may be defined by a hole provided in a top side of the stamp. Thanks to the hole, when the stamp is removed from the unhardened concrete, the hole functions as a pressure-relief or pressure-equalizing valve eliminating undesirable distortion of the unhardened concrete and ensuring formation of desired dome-shaped concrete projections.

Abstract: A method of construction of structures such as large, decorative pots, water features and outdoor free-standing fireplaces. The method comprises pouring a concrete base to which a skeletal reinforcing structure in the desired shape is set. Thereafter, metal screen and a cementitious material is applied over the skeletal structure to form a shell. Openings may be formed either when shaping the shell or later by cutting away areas of the steel skeletal structure. Suitable decorations such as graphics may be applied using stains, dyes or carving techniques.

Abstract: A method for securing a branch assembly to a “live” pipeline. An upper part of the assembly incorporating the branch is positioned on the pipeline over a containment ring located on the pipeline and within which is an annular seal surrounding an area from which the branch is to extend. A lower part of the assembly is positioned on the pipeline beneath the upper part and the two parts are secured together so that the seal is compressed and an annular space is left between the two parts and the external surface of the pipeline. Grout is injected into the annular space and cures to bond the two parts forming the branch assembly in position on the pipeline. The use of grout avoids having to use welding techniques on a “live” pipeline. A coupon can be cut out of the pipeline, via the access through the branch.

Abstract: Shuttering elements (1, 20) for the construction of a hemispherical building are disclosed, comprising webs (10) along the side edges (4, 5) thereof. The webs (10) project from the underside (8) of the shuttering element (1, 20), facing what is to become the building interior (36). The individual shuttering elements (1, 20) may be connected using the webs (10), by means of quick-fasteners (12, 13) to produce the complete shuttering and are multiply re-usable. The invention further relates to a method for the construction of a hemispherical building.

Abstract: A riser section and cover is disclosed. The riser section has a smooth cylindrical sidewall surface, a tapered end and a channel end, a removable anchor tab and bosses and ribs on the inside of the sidewall. The riser sections are stackable. The cover has a channel end to removably connect to a riser section. The cover has stowable handles and posts extending from a bottom surface that define wells open at a top surface which fit into the wells of another cover. A bracket is disclosed to releasably secure and position a cover with attached riser section on a concrete form wall.

Abstract: In accordance with the present invention there is provided an insert for placement in a mold for forming a concrete jar to form holes in the interior of the concrete jar for receiving steps and a method for forming holes in the interior of a concrete jar or manhole casing for receiving steps to enable a worker to climb into and out of said concrete jar or manhole casing, the insert including two hollow tubular anchors, each of the anchors having a first end and a second end, each of the anchors being equal in length, a rigid frame connected to the first end of each of the two anchors, the frame having a front side and a back side, the two hollow anchors extending from the front side of the frame, the anchors being parallel to each other, and the anchors being closed at the first end and open at the second end.

Abstract: A method of increasing the structural strength of a load bearing member such as a pile (12), particularly for the purpose of repairing a damaged pile, includes the steps of securing a rigid, structural sleeve (17) around the pile (12) and spaced therefrom to form an interspace (18), filling the interspace (18) with an expansive filler (19), and allowing the filler (19) to set and expand in the interspace (18) to a prestress of at least 3 MPa and impose tensile hoop stresses in the sleeve (17) and corresponding compressive hoop stresses in the pile (12) to enhance the load transfer between the pile (12) and the sleeve (17).

Abstract: A concrete column forming tube is provided for receiving poured concrete therein to produce a concrete column and which eliminates spiral seam lines and other undesirable characteristics on the outside surface of the formed concrete column and provides a construction which may be easily removed from the concrete column. The forming tube includes a spirally-wound cylindrical paper tube including multiple plies of paper adhered together, a centrifugally-cast plastic coating sprayed on an inside wall surface of the spirally-wound paper tube for producing an inside coated surface having a thickness and smoothness sufficient to eliminate spiral seam lines and other undesirable characteristics, and a tear strip positioned between the inside surface of the cylindrical paper tube and the plastic coating before centrifugal-casting and extending longitudinally of the forming tube over the entire length thereof and having a predetermined width and readily detachable from the plastic coating.

Abstract: A process for restoring the damaged bottom of a storage tank. The process is initiated by preparing a slurry containing unconsolidated solids and a gelation solution. The gelation solution includes an aqueous liquid solvent, a crosslinkable polymer, and a crosslinking agent. The slurry is placed on the internal bottom surface of the storage tank in a sufficient volume to fully cover the surface. The gelation solution is then gelled substantially to completion in the storage tank to form a gel that binds the unconsolidated solids and converts the slurry into a hardened conglomeration. The hardened conglomeration provides a coat over the internal bottom surface of the storage tank to prevent further damage to the bottom of the tank and leakage therethrough.

Abstract: A building structure that is a one-piece extruded building that can simultaneously build inner and outer walls, roof, reinforcement and optionally even floors. Said structure is made up as a composite of an inner and outer encapsulating building material that provides structural strength, plus an inner core material composed of a highly expanding closed cell foam material for insulation. The building material is polymer based, but can also be a polymer-concrete, wherein traditional fibers are minimized and substituted for other aggregates. The polymer in the encapsulating material can have the catalyst encapsulated and premixed into a slurry form activated at the injection point by mechanically rupturing the capsule, or can be mixed and added at the injection point with a specially designed metering injectors. All comers and joints allow the encapsulating building material to join between inner/outer walls forming columns and evenly spaced beams or studs made from the same encapsulating building material.

Abstract: Method of producing a filter floor for treating water, comprising a structure made of girders or columns supporting a slab which has a number of orifices intended to take suction strainers, characterized in that the concrete of the said structure and of the slab is cast directly in the filter liner, the said structure and the lower part of the slab being shaped by one single design of lost formwork.

Abstract: Forming concrete piles with an enlarged base for structural foundations for buildings. The invention involves: a) drilling a bore hole with an auger; (b) pumping fluid concrete into the bore hole through a channel in the auger whilst retracting the auger from a lower portion of the bore, such that the lower portion of the bore becomes filled with a volume of fluid concrete; (c) applying a pressure to the volume of fluid concrete by at least partly reinserting the auger into the lower portion of the bore, such that the applied pressure causes the volume of concrete to expand radially, thereby increasing the diameter of the lower portion of the bore; (d) retracting the auger from the remainder of the bore whilst pumping further concrete into the bore, such that the bore fills with concrete and forms a concrete pile with an enlarged base. The enlarged base area provides greater load bearing capacity.

Abstract: A method for inverting the convex configuration of a liquid-product storage-tank bottom is described for providing greater efficiency in the removal of undesirable materials that normally accumulate on the tank bottom. A layer of material having plastic properties is placed over the conventional tank bottom except for at least one section from the center of the tank base to the edge. The material with plastic properties hardens over time, thus producing a new bottom having a center at a level below the level of the edge. The part over which the material having plastic properties was not placed forms a flow gutter which leads the liquids and sediments which have to be drained off to the edge.