Concrete Cladding

Description

FIELD OF THE INVENTION

This application relates to cladding for concrete mixtures, in particular to cladding in the form of caissons for the deposition of concrete mixtures.

BACKGROUND OF THE INVENTION

Concrete mixtures are workable when poured and then harden over time and cure. Workable concrete mixtures are generally poured into forms, often made from plywood, which are removed as the concrete mixtures cure and harden. Those plywood forms are temporary cladding for the concrete mixture.

Marine environments pose unique challenges for pouring and curing concrete mixtures. Traditional caissons, such as “Cast in place concrete pile with precast type caisson”

Korean publication #20120012504A, are used to present a water-free, open-top, space in which to pour a concrete mixture in a marine environment.

Traditional caissons are also used outside of marine environments in situations where the caisson contributes to the structure being constructed in a manner that temporary plywood forms do not. “Open-cell caisson structure and construction method” WO publication #2017039254A1 discloses a terrestrial system for using caissons as permanent cladding and structure.

Both marine concrete and terrestrial concrete needs can benefit from the use of reactive concretes. Reactive concretes are traditional concretes with the addition of precursors to allow for certain beneficial mineralization while exposed to its environment. Jackson, U.S. Publication No. 20220089484 discloses a reactive concrete with a stated benefit of enhanced longevity based on these principles, but without the benefit of cladding.

There is a need for a cladding, including in caisson format, for concretes, especially reactive concretes, where the cladding enhances the curing capacity for the reactivity in a measured manner, including in marine and seawater environments.

Structures such as seawalls, breakwaters, and offshore platforms are constantly exposed to the harsh and corrosive conditions of marine environments including seawater, as an example. The corrosive nature of seawater can lead to the deterioration of traditional materials, including steel, wood, and conventional concrete, compromising the structural integrity of marine infrastructure, and often requiring frequent maintenance and repair.

Reactive concretes, such as Jackson, U.S. Publication No. 20220089484, have emerged as promising solutions in marine infrastructure. These specialized concretes are specifically designed to react with seawater or salt water, forming mineralized compounds that enhance the strength and durability of the structure over time. The maturation process of reactive concretes gradually improves integrity and performance, resulting in an extended service life and reduced maintenance requirements.

Unfortunately, reactive concretes can take a significant amount of time to mature. Viable systems and methods for the installation of advanced reactive marine concretes and construction utilizing such concrete is costly, labor intensive, and geography-dependent. It is the object of this invention to provide an economical, labor-efficient, and geographically independent solution to cladding concretes while they take the time to mature for protection and not to interfere with helpful concrete reactivity.

SUMMARY OF THE INVENTION

A preferred embodiment of the invention incorporates the cladding of the invention as the walls of a caisson in the shape of a floatable form for a special type of concrete generally referred to as reactive concrete. The caisson is designed to be submerged in seawater, acting as a stay-in-place cladding for a reactive concrete mixture.

A primary benefit of this caisson form is its ability to be floated to the desired location. In use, a caisson incorporating the invention is filled with a reactive concrete payload mixture and then submerged. The caisson includes a series of tubes, channels, or holes (hereinafter referred to as perforations) through the walls with diameters of approximately ≤1″, which are initially plugged or blocked, such that the caisson may float, either with or without additional floatation devices.

Before the placement of the caisson or during the process, the plugs are pulled out, allowing water or seawater to enter. This interaction, for example, between seawater and the reactive concrete within the caisson triggers a maturation process in the reactive concrete, which continues over several months or even years. This extended maturation period further enhances the strength and durability of the concrete structure.

The presented caisson form for concrete, including reactive concrete improves upon traditional construction methods for marine structures like seawalls. Conventionally, these structures require the construction of a cofferdam to allow for dry setting, where concrete forms are established, reinforcement is placed, and concrete is poured and cured-all in the absence of ambient water. This process is labor-intensive and results in structures with a lifespan of 25 to 40 years, due mainly to material and construction method limitations. In contrast, the new caisson form of the invention simplifies the construction process. That process involves transporting the caisson to the site, filling it with reactive concrete, and allowing it to be set in place. This method integrates the caisson with the reactive concrete through a mineralization process, enhancing durability and significantly extending the concrete structure's lifespan to potentially up to 200 years, drawing from the extreme durability and long life of Roman-style reactive concrete. This approach eliminates the need for cofferdams and provides a more durable, long-lasting solution for marine construction.

From an environmental perspective, the invention offers notable benefits-by reducing the time, energy, and fuel needed for construction. The invention also introduces biocompatible surface textures that encourage the growth of marine life, supporting ecological balance. Additionally, it provides a scalable solution through the potential for mass production, addressing the demand for marine structures, environmental conservation, and considerations regarding climate change.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric drawing of the cladding in the preferred caisson form.

FIG. 2 is a side cross-sectional view of the caisson of FIG. 1, drawn at Lines AA, as filled with a concrete mixture.

FIG. 3 is a top cross-sectional view of the caisson of FIG. 1, drawn at Lines BB, as filled with a concrete mixture.

FIG. 4 is an isometric view of the cladding of the invention not incorporated into a caisson.

FIG. 5 is a cross-section view of the cladding wall of the invention incorporating a plug and a mesh.

FIG. 6 is a cross-section view of the cladding wall of the invention incorporating a foam plug.

DETAILED DESCRIPTION:

The present invention relates to a mechanism that significantly enhances the curing process and resulting structural durability of concrete, including reactive, slow-curing concretes, particularly in marine environments. By including a cladding interface between concrete mixtures and their environments, this system aims to alleviate prevalent issues with marine concrete such as accelerated corrosion, and diminished lifespan, which often plague traditional concrete infrastructures in such settings. Utilizing a combination of novel materials and construction methodologies, the system of the invention establishes a protective layer over the concrete structures. This layer is crucial for extending the structural service life of reactive concrete by effectively countering environmental adversities while allowing essential marine hydration to assist the reactive concrete mechanism's curing process.

Put simply, and in the context of its use, the invention describes an open-top pre-cast concrete container of sufficient dimensionality to enclose and support, for transport and placement, a significant amount of concrete, including reactive or other slow-curing concrete material. The container has perforations distributed across its exterior. These perforations are channels that run from the exterior to the interior such that once submerged, water or seawater can come in contact with the reactive concrete residing in the form upon submersion. Prior to submersion, and while loading the concrete mixture, these perforations can be plugged.

These caisson forms can be filled prior to being transported to a construction site, as with any precast concrete implement, or they may be transported to the site, and then filled with reactive concrete whereby they submerge.

A greater understanding of the system can be achieved by referencing the figures and enumerated features in the drawings accompanying the disclosure.

A first embodiment of the cladding system, demonstrated in FIG. 1, introduces the form 100, which doubles as a caisson for concrete application. This embodiment showcases the caisson form 100 acting as a semi-permanent cladding for the concrete mixture 320, effectively embodying the dual purpose of structural support and protective layering. The form accommodates concrete mixtures within an internal cavity 110, facilitating an integrated approach to construction that enhances both the efficacy and longevity of the installation.

Addressing the issues of corrosion, reduced lifetime, and sustainability prominent in marine construction, this invention enables the use of reactive marine concrete mixtures. These mixtures, characterized by slower curing rates, autogenous healing abilities, and lower carbon footprints than concrete mixtures made primarily from traditional ordinary Portland cement (“OPC”), are enabled via the cladding system of the invention 100 to leverage their reactivity for environmental and economic benefit. This embodiment, as outlined, addresses the limitations inherent in marine concrete applications by facilitating the extended curing and maturation cycle of advanced concrete technologies that improve longevity and reduce ecological impact.

The preferred embodiment of the caisson form 100 made from the cladding 101 of the invention is an open-top container made from OPC or other fast setting or curing concrete, with sides/walls 102 of about four inches of thickness, and bottom/floor 201 of about six inches of thickness, the caisson form 100 having an exterior dimension of about forty-eight inches high, forty-eight inches wide, and about forty-eight inches long. To float unassisted, the walls and floor need to be of a proportion that they displace enough water to float the caisson. Thus, the thickness of a wall needs to be about 8% to 10% of the length of the wall, and the area of the bottom of the caisson needs to be about 12% to 15% the average area of any adjacent wall. While box-shaped caissons are a preferred embodiment, the shape of the caisson is constrained only in that it has walls, a floor, and an open top. Optionally, as seen in FIG. 2, the bottom floor 201 of the caisson is configured with two channels 130 and 220 running the length of the caisson form 100. These channels are about three inches deep and about six inches wide, each centered about eighteen inches from the center of the caisson form 100. These channels 130 and 220 allow for movement of the caisson using a standard forklift or crane rigging. These caisson dimensions create an internal cavity 110 of forty inches wide by forty inches long by forty-two inches high to accept a concrete payload mixture 320.

While the preferred embodiment is a square or rectangular polyhedron, the caisson can be of any shape, such that it can be filled from the top—this includes but is not limited to cylindrical, conical, or polyhedral. In a preferred embodiment, the walls 101 of the caisson form 100 are the cladding of the invention. the walls 101 are perforated by a series of holes or perforations 120 and 310, each perforation having an approximate diameter of about between one half inch to two inches. The choice of this size range is deliberate, designed to permit the influx of water yet obstruct the egress of the concrete composition. These channels 120 and 310 and 530 are initially plugged 210 and 540 during transport and placement. Accordingly, each wall 101 of a caisson 100 integrating the described technology is provided with a plurality of holes or perforations 120, 310, and 530. In a preferred embodiment, these perforations are systematically arranged in a matrix of three horizontal lines and four vertical columns, spaced to ensure uniformity. This layout is designed to facilitate the movement of water or seawater into the core concrete volume 320, thereby enabling the consistent maturation of the encapsulated reactive concrete. In other embodiments, the diameter of the perforations 120, 310, and 530, depending upon the thickness of the walls, may be as wide as about 3 inches in diameter to as narrow as about ½ inch in diameter and the arrangement of the perforations can include any pattern wherein they are evenly distributed. Put another way, the holes may be 15% to 40% the thickness of the walls.

In one embodiment, the caisson form 100 may have reinforcement within its walls consisting of rebar 300 or other reinforcing bar or rod, as is a common practice in concrete forms. Optionally it may be reinforced 300 with alternative materials such as basalt or fiberglass rods or composite materials made of a polymer reinforced with fibers of which the polymer is usually an epoxy, vinylester or polyester thermosetting plastic that is combined with a fiber, such as glass or carbon, in order to make the polymer strong and rigid 200. These non-corrosive materials enhance the structure's longevity and biocompatibility. This reinforcement modification is aimed at enhancing the structural integrity and stiffness of the caisson form, leveraging the distinct advantages offered by these materials over traditional rebar, including improved biocompatibility and resistance to environmental degradation.

Previous to placement and filling, the perforations 120, 310, are plugged with either a removable plug 210, 540, or with a biodegradable and biocompatible foam or membrane plug 630.

Optionally, the opening of each perforation 120 and 130 in a wall 101 on the side of the wall adjacent to the concrete mixture 110 and 420 and 520 and 640 includes a mesh that obstructs the passage of the concrete to the perforation(s). Optionally, a semi-permeable fabric may be used to the same effect as the mesh 550. It should be understood that if the perforation is significantly deep, for embodiments wherein the cladding wall is relatively thick, the mesh 550 may not be needed, as the interior concrete will have intruded into the interior of the perforation somewhat, and be sufficiently solid, capable of limiting the immediate ingress of water or seawater from the exterior.

If a reactive concrete mixture is used in the caisson 100, the holes 120 allow for the reaction between the reactive concrete 320 and water or seawater resulting in the formation of compounds that greatly enhance the structure's strength and durability, as explained in Jackson op cit. This natural curing process gradually improves the overall performance of the concrete 320, resulting in a stronger final product that outlasts (and may even incorporate) the caisson form 100 through chemical mineralization of the caisson form 100 into the interior structure 320, and through biomineralization, as explained in Jackson op cit.

It should be recognized that the OPC nature of the caisson form 100 can be replaced with a variety of other concrete designs, including, but not limited to other concrete species such as, calcium sulfoaluminate cement, magnesium phosphate cement, and alkali-activated materials (including fly ash, slag and combustion residue based geopolymers).

It should further be recognized that the exterior surface of the cladding 410 or caisson 102 is of enhanced biocompatibility when it is appropriately textured in a manner that allows organisms better purchase and if it exhibits a surface pH between 6 and 11.

The present invention provides a versatile and innovative concrete cladding system that effectively addresses the shortcomings of traditional concrete methods in marine and other challenging environments. Through its advanced design and intentional material choices, the system not only enhances the strength and durability of concrete structures but also offers ecological benefits and improved efficiencies.