TECHNICAL FIELD
The present disclosure relates generally to concrete forms and related concrete construction technology, and relates more particularly to a concrete form system having an outer form with a structural foam material and an outer protective skin material.
BACKGROUND
Construction technology related to the pouring, forming, and curing of concrete to build foundation slabs, footers, and basement walls has advanced significantly over the years. While some of the basic materials and procedures for creating a concrete structure have been little changed for literally more than a thousand years, more recently highly sophisticated materials, science, and construction engineering have been applied to certain apparatuses, notably forms, used in pouring concrete.
One known technique relates to the use of foam panels to contain concrete in its uncured, flowable state in a particular shape so that the concrete can retain that shape once cured. Foam panels have the advantage of being relatively lightweight and easy to handle, and can provide insulation about the periphery of the structure to be formed. Foam panels of known design have various shortcomings relative to certain applications. For instance, foam panels are typically removed once curing of the poured concrete is complete, leaving an unsightly and unfinished exterior surface that must be painted, obscured, or otherwise treated to produce a suitably aesthetically pleasing finish.
SUMMARY
In one aspect, a concrete form system includes inner and outer forms coupled together via a plurality of connecting webs. The outer form includes a structural foam material forming an inner surface, facing the inner form, and structured to contact concrete poured into a space between the inner form and the outer form. The outer form further includes a protective skin material in contact with the structural foam material and forming an exposed outer surface of the outer form.
In another aspect, a method of making a concrete form is disclosed. The method includes production of a substantially rectangular body having a plurality of peripheral edges extending about a first and a second body side of an outer concrete form from a structural foam material, applying a protective skin material in liquid form to the first body side such that the skin material adheres to the structural foam material on the first body side, and packaging the substantial rectangular body for shipping with the protective material adhered to the structural foam material located upon only the first body side.
In still another aspect, a method of constructing a foundation is disclosed, the method including assembling a concrete form system such that an inner form and an outer form are supported in parallel spaced apart relation, positioning the concrete form system upon a footing, pouring uncured concrete into a space extending between the inner and outer forms such that upon curing the concrete forms a solid wall extending upwardly from the footing, and orienting the outer form during assembly and positioning such that an inner surface formed from a structural foam material of the outer form faces the space and is contacted by the poured concrete, and an opposite surface formed from a protective skin material of the outer form is exposed and faces outwardly of the foundation.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a top diagrammatic view of a concrete form system and a foundation system at one stage of construction, according to one embodiment;
FIG. 2 is a sectioned side diagrammatic view of a concrete form system at one stage of construction, according to one embodiment;
FIG. 3 is a detailed enlargement of a rectangular body, according to one embodiment; and
FIG. 4 is a diagrammatic view of stages of making a form for use in a concrete form system, according to one embodiment.
DETAILED DESCRIPTION
Referring to FIG. 1, there is shown a concrete form system 20 according to one embodiment. Form system 20 may be part of a foundation system 10 including a footer 12 of poured and cured concrete within a trench in the ground. An aggregate 14 of any suitable kind can be placed adjacent to footer 12 to form a subgrade, upon which a poured concrete foundation 13, typically in the form of a slab is to be poured. A cutout 19 of foundation 13 illustrates aggregate 14 underneath and adjacent to foundation 13. It should be appreciated that foundation system 10 could be used for supporting a residential living structure, a light industrial installation, or even a bare concrete slab to serve as a parking lot, or for any other conceivable purpose. In a practical implementation strategy, plumbing pipes 18, electrical service wires, or other installations may be located within or upon aggregate 14 and thus covered by concrete foundation 13 once formed.
Referring now also to FIG. 2, there is shown a sectioned diagrammatic view of foundation system 10 and form system 20 along line 2-2 of FIG. 1. System 20 may include an inner form 22 having a first substantially rectangular body 24 with a top peripheral edge 26 and a bottom peripheral edge 28. System 20 may also include an outer form 30 having a second substantially rectangular body 32 with a top peripheral edge 34 and a bottom peripheral edge 36. A plurality of connecting webs 38 couple together inner form 22 and outer form 30 in spaced apart relation, with a space 48 extending therebetween. The coupling together of inner form 22 and outer form 30 is also such that rectangular bodies 24 and 32 are oriented parallel to one another at least in a practical implementation, and bottom peripheral edges 28 and 36 are positioned in a common plane or only modestly out of plane, for positioning system 20 upon footer 12. In one implementation, the components of form system 20 can be assembled prior to placement upon footer 12, either at a job site or even at a remote assembly facility. An alignment channel 40 extends along bottom peripheral edge 36, and can be fastened by any suitable means such as an adhesive or fasteners to the concrete forming footer 12. A fastening bolt 41 is shown as an illustrative example. In a practical implementation strategy, form system 20 may have the general shape of a polygon, extending about a plurality of sides of the foundation system 10. Form system 20 can therefore contain and direct the flow of concrete 16 not yet in a cured state, filling space 48 to form a stem wall or the like that is positioned upon footer 12.
In FIG. 2, space 48 is shown filled part way with concrete 16, which will typically be poured to fill space 48, and flow or extend over the top of inner form 22 to make contact with aggregate 14. Contact between portions of the poured concrete forming the stem wall and forming the slab is not visible in FIG. 2 due to the section planes chosen. In some instances a gap or intervening layer of a different material could be positioned between the stem wall and slab portions. Inner form 22 may have a shorter height 27, height 27 being the distance from footer 12 to top peripheral edge 26, than height 35 of outer form 30, height 35 the distance from footer 12 to top peripheral edge 34. It can thus be appreciated that a horizontally extending foundation 13 once cured will be supported upon aggregate 14, while a downwardly extending stem wall may be formed integrally with the foundation 13 and at least in certain instances extends peripherally about aggregate 14 at an outer edge of foundation system 10, to contact footer 12 in between inner form 22 and outer form 30. The relative height 27 of inner form 22 to height 35 of outer form 30 may facilitate the general shaping of the stem wall so as to allow concrete 16 to flow over inner form 22 and come into contact with aggregate 14 when poured into space 48, or flow over inner form 22 in an opposite direction to fill space 48. The difference between height 27 and height 35 may depend on a desired thickness of foundation 13. As concrete 16 may flow over inner form 22 but not outer form 30, height 35 may be at least the total of height 27 and the desired thickness of foundation 13. For example, if the height 35 of outer form 30 is 4 feet and the desired thickness of foundation is 6 inches, the height 27 of inner form 30 may not be greater than 42 inches. Outer form 30 may be shaped so a kicker brace or the like 42 may receive top peripheral edge 34 and support the same during pouring of concrete into space 48. An additional channel piece 52 may be provided as shown end-on in FIG. 1 for positioning at a corner where adjacent panels of outer form 30 are adjoining, extending vertically from footer 12. It can be seen that channel piece 52 can include channels generally extending in a parallel configuration but opening so as to define approximately a right angle to receive the rectangular bodies 32 of outer form 30 at the corner. An analogous channel can be provided for inner form 22 and is shown in FIG. 1 via reference numeral 54.
Outer form 30 may include a structural foam material 50 that forms an inner surface 44 of substantially rectangular body 32, faces inner form 22 and is thus structured to contact concrete 16 poured into space 48. Structural foam material 50 may be a one-piece body and is to be understood as structural in that it does not collapse under its own weight, at least when shaped and dimensioned according to generally analogous building products. For instance, outer form 30 might be from about 3 feet wide or tall to about 6 feet wide or tall, from about 2 feet long to about 16 feet long, and from about ½ inch thick to about 12 inches thick. It will be appreciated that the width and length and thickness of body 32 will typically be chosen based upon the intended service application, and accordingly relatively shorter or narrower forms constructed according to the present disclosure might be relatively thinner, whereas relatively taller or wider forms might be relatively thicker. Specific examples of suitable materials for constructing outer form 30 are further discussed herein.
Referring also to FIG. 3, there is shown a detailed enlargement of a portion of outer form 30 in greater detail. Outer form 30 further includes a protective skin material 56 in contact with structural foam material 50. In FIG. 2, protective skin material 56 is peeled back from structural foam material 50 to illustrate the relatively greater flexibility of material 56 versus material 50. In the present embodiment, protective skin material 56 may be in contact with only one side of structural foam material 50, with inner surface 44 remaining free of protective skin material 56 allowing inner surface 44 to contact concrete 16 freely. Inner surface 44 may therefore be in fluid contact with uncured concrete 16 allowing concrete 16 to flow into any voids or pores 60 in structural foam material 50. The ability of uncured concrete 16 to fluidly contact inner surface 44 without any barrier such as a polymeric coating or other material allows concrete 16 to form a relatively stronger mechanical bond with structural foam material 50 when curing, providing structural rigidity to form system 20, and may increase durability and longevity of system 20. In some embodiments, there may additionally be a chemical bond between concrete 16 and structural foam material 50. A strong bond between outer form 30 and concrete 16, especially where an outer surface 46 may be textured to have visual or stylistic characteristics as will be discussed further herein, may have certain advantages as will be appreciated by those with skill in the art.
Protective skin material 56 forms the exposed outer surface 46 of outer form 30 located opposite inner surface 44. In a practical implementation strategy, rectangular body 32 may consist essentially of structural foam material 50 and protective skin material 56, although certain additives such as fire retardants, anti-fungals, colorants, pesticides, or still other materials might be part of rectangular body 32. The outer surface 46 formed by protective skin material 56 may be substantially smooth in many instances, and smoother than inner surface 44, but can also be roughened or textured in others. In FIG. 3, indentations or slots 59 are shown in a regular and alternating arrangement with protrusions 57, a structure that might be seen where a faux brick or stone finish is formed on skin 56. It is contemplated that material 56 might be applied, as further discussed herein, and textured via mechanical indentation means or another technique prior to completing curing, although the present disclosure is not thereby limited. Thus, embodiments are contemplated where a wood grain, a stone grain, a brick pattern, or still other visually and aesthetically observable properties are present. Top peripheral edge 34 and bottom peripheral edge 36 may be formed of structural foam material 50. Since surface 44 will typically be formed of the structural foam material, the only protective skin material used may be the protective skin material that is applied to one side only of body 32.
It is also contemplated that structural foam material 50 may include a foamed polymeric material, and protective skin material 56 may include a continuous polymeric material adhered to the foamed polymeric material. Further still, the continuous polymeric material may be chemically bonded to the foamed polymeric material. Examples of suitable continuous polymeric materials are certain materials commonly applied by plural component spray, and including a polyurethane, a polyurea, an epoxy, or a hybrid of any of these. Foamed polymeric material comprising material 50 may include a polyisocyanate, polyurethane, or polystyrene, for example. Inner form 22 may be any suitable material desirably but not necessarily having some resistance to degradation over time. The material of which inner form 22 is made will typically be different than the material of which outer form 30 is made, and could include any polymeric material suitable for permanent installation in ground contact conditions.
It can also be seen from FIG. 3 that an interface 58 resides between material 50 and material 56. Material 50 may contain voids or pores 60, commonly associated with a cellular foam material. It will be seen at interface 58 that certain of the voids or pores 60 may be open such that material 56 intrudes therein. It will thus be appreciated that some degree of mechanical interlocking between material 50 and material 56 may occur. As will be further discussed herein, material 56 is applied in the form of a liquid or liquids, thus imparting the tendency for flow of the liquid into any voids or pores in material 50 and interlocking with the same upon curing. Depending upon the materials selected which will typically and by necessity be chemically compatible, polymer crosslinking between material 56 and material 50 may occur. Those skilled in the art will appreciate the cure time and/or hardening time of foamed polymeric materials, and in particular extruded foam polymeric materials, can be such that application of material 56 in plural component liquid form can be timed to enable some chemical bonding between the materials 50 and 56, and even making available some flexibility in the extent to which chemical bonding is sought. In other words, while it is contemplated that prefabricated and fully cured and/or hardened foamed polymeric materials can be sprayed with plural component coatings according to the present disclosure, in many instances the plural component polymeric material coatings can be sprayed onto the foamed polymeric material prior to completion of curing and/or hardening, in some instances substantially prior to completion of curing and/or hardening and in others when curing and/or hardening of the foamed polymeric material is substantially completed. Desirable properties relating to the manner in which materials 50 and 56 interact and stick together can be empirically determined.
Referring now to FIG. 4, there is shown an example a production assembly 100 for producing rectangular bodies 24, 32 having a protective skin material 56 that can be used in constructing foundation system 10 or form system 20 according to the present disclosure. Process flow in the production assembly generally flows from an extruder 64 to a sprayer 72 and then to a cutter 68 as demonstrated by process flow arrows in FIG. 4. A texturing device (not shown) could also be part of production assembly 100, and positioned so as to form texturing as contemplated herein on skin 56, potentially while soft and/or prior to completing curing. Raw material of conventional type can be fed into a hopper 62, and then heated and processed to a foamed or foamy state in extruder 64. Extruder 64 will generate an extrusion in the form of a foam body 66 that can be cut via cutter 68 to a desired dimension, foam body 66 having a first body side 67 and a second body side 69. For example, according to the present disclosure, cutter 68 may be configured to cut foam body 66 for use as rectangular body 24 and/or rectangular body 32. In some embodiments, foam body 66 may be formed of structural foam material 50. It can be seen from the process flow of FIG. 4 that cutter 68 will typically be employed after application of plural component spray 70. In other words, given a relatively fast cure time commonly on the order of no more than several minutes for many plural component sprays, cutting of the extruded foam body with adhered skin material will typically occur after the skin material has been applied. Plural component spray 70 includes relatively fast-curing liquids, which, when applied to foam body 66 will cure rapidly, forming protective skin material 56. As discussed herein, plural component spray 70 may chemically bond to foam body 66 when curing. Sprayer 72 may be structured so as to spray plural component spray 70 on first body side 67 of foam body 66 while leaving second body side 69 free of plural component spray 70. An optional cutter 74 is shown, however, that might be additionally or alternatively used to cut foam body 66 prior to application of the plural component spray 70. With the plural component spray 70 applied only upon first body side 67 of the extruded foam body 66, resulting in a coated foam body 76. Once cut to length coated foam body 76 can be packaged for shipping. While embodiments are contemplated where a number of packaged panels will be strapped to a pallet or the like 78, it will be appreciated that no limitation to the manner of packaging is contemplated herein, and in some instances no packaging at all could be used without departing from the full and fair scope of the present disclosure. From the foregoing description and that to follow, it will be apparent the present disclosure provides solutions to various shortcomings in known systems. On the one hand, the present disclosure provides for a finished exterior and protective surface of the form system. Physical damage, soiling and UV damage to the insulating foam is avoided. Those skilled in the art will be familiar with the relatively long periods of time that can occur between various stages of construction. Seasonal breaks and long periods of bad weather can leave insulating concrete forms exposed and likely to deteriorate if some protection is not provided. A separate crew in addition to the concrete contractor is often retained to install some sort of protective shielding exterior to the concrete forms. In some housing developments, some homes may be finished and ready for showing to prospective buyers while others are in various states of construction. Exposed foam board and the like can be considered unsightly, especially where splashed with mud, torn, dented, or otherwise degraded. The present disclosure overcomes these and other shortcomings of standard approaches.
The present description is for illustrative purposes only, and should not be construed to narrow the breadth of the present disclosure in any way. Thus, those skilled in the art will appreciate that various modifications might be made to the presently disclosed embodiments without departing from the full and fair scope and spirit of the present disclosure. For instance, while certain practical implementation strategies are disclosed herein relative to specific material compositions, it will be appreciated that the present disclosure is not strictly limited as such and other possible combinations and mixtures of materials will be apparent to those skilled in the art. Other aspects, features and advantages will be apparent upon an examination of the attached drawings and appended claims.
Patent Application
20170101775
