Static structures (e.g. – buildings) – With synthetic resinous component – Foam
Reexamination Certificate
1998-07-17
2002-07-02
Friedman, Carl D. (Department: 3635)
Static structures (e.g., buildings)
With synthetic resinous component
Foam
C052S588100, C052S783170, C052S798100, C052S439000, C052S749100, C428S182000
Reexamination Certificate
active
06412243
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention provides a lightweight modular composite building assembly system with components capable of sustaining heavy axially applied loads.
2. Description of the Related Art
Polymer foam materials, e.g., sheets or blocks of low density expanded polystyrene, polyurethane and the like, have been widely used in the construction industry for purposes of building insulation. Plastic foam in the form of panels or foamed-in-place polyurethane has been used, for example, to provide an insulative wall or roof sheathing material, as perimeter insulation for floor slabs, as an insulative core layer sandwiched between structural components such as plywood, wall board or metal, as disclosed in U.S. Pat. No. 3,583,123, or as insulative layers surrounding poured concrete, as for example disclosed in U.S. Pat. No. 5,664,382.
It has also been proposed in the prior art to utilize plastic foam materials in combination with other structural components to prepare structural building panels or blocks which are said to be capable of structural rigidity especially from lateral loads or other stresses applied to them. Examples of such structural components may be found in U.S. Pat. No. 5,638,651 which discloses an interlocking insulated panel having an expanded polystyrene core sandwiched and glued between oriented strand board (OSB) and further containing a pair of metal channels glued to opposite sides of the core and partially embedded in the core. The metal channels are said to impart structural strength to the panel. U.S. Pat. No. 4,903,446 discloses a prestressed plastic foam structural member prepared by forming a grid-work of rope-like or wire tendons maintained in a tension condition within a mold, and encapsulating the grid-work with expandable plastic foam to form a lightweight structural member.
Also, U.S. Pat. No. 4,351,870 discloses a building panel material comprising a centrally disposed convoluted sheet stiffening layer of high strength material, such as metal or plastic, laminated on each side with an adhered sheet of expanded plastic material such that the expanded plastic sheet contacts the convoluted crests and troughs of the centrally disposed sheet. The panel may also contain coatings on the outer foamed plastic surfaces thereof which are of a decorative or weather-proofing nature, as well as combustion-inhibiting layers positioned on one or both sides of one or both expanded plastic sheet layers.
Further, U.S. Pat. No. 5,448,862 discloses a prefabricated foamed plastic staircase where vertical slots are provided for the insertion of reinforcing steel rods meant for embedment in concrete beams below the surface to provide stiffening for the overall structure but no assistance to the function loading on the tread surfaces.
Other related structures are disclosed in U.S. Pat. Nos. 4,159,681; 4,241,555; 4,558,550; 4,611,450; and 4,774,794.
In applications such as described above, the expanded plastic material serves two primary roles:
a) an insulation layer which imparts both insulative value and moisture barrier properties to the structure, and/or
b) a matrix imparting three-dimensional shape to the structure and providing a platform for mounting or assembling structural components and/or fire retardant or finishing layers.
In none of these applications are the main structural components intended for the primary purpose of supporting or bracing axial loads directly applied to an encapsulated rigid structure, nor is the expanded plastic material by itself intended to, or capable of, supporting high compressive or axial loads applied thereto, or even capable of contributing significantly to the strength of the main structural components which are designed into such systems as the load and stress-bearing components. It is obvious that, in all of the prior art, the general intent of the foam is to provide diaphragm rigidity to a planar configuration from lateral forces, with no active purpose in the support of directly applied longitudinal axial loading in compression. And while such diaphragm rigidity may have been accomplished, the end product results are limited to purposes of rigid building enclosure rather than as the main building structural supporting elements.
For example, consider a steel wire mounted vertically between the plates of a press. The wire will initially resist a certain amount of compressive axial force applied. As more pressure is applied, the wire will strain and begin to buckle and eventually bend or break at the point of compressive tensile failure. Now consider the wire inserted longitudinally at the axis of a cylinder of STYROFOAM™ plastic about the size of a wooden thread spool such that the wire tips are exposed at the base and top of the cylinder. As the main support for the structure, the axially disposed wire will be subjected to the same forces as described for the unsupported wire, but will to some degree be laterally supported by the STYROFOAM™ matrix. Since the styrene foam can support only about 20-25 lbs per square inch compressive force after 10% deformation, the wire remains the main structural component. The tendency of the wire to buckle is, however, somewhat restrained by forces generated as the wire bows and compresses the surrounding foam in the direction of bowing, but there is no support for the wire on the side opposite the direction of bowing and the wire will eventually rupture the compressed foam and fail as described above. This is essentially the same phenomena involved with the prior art structures described above where structural layers are laminated to or encapsulated within foam layers and the resulting structure subjected to stress.
Now consider that same steel wire coated with an adhesive and inserted longitudinally at the axis of the STYROFOAM™ cylinder such that the wire tips are exposed at the base and top of the cylinder and the shaft is circumferentially bonded to the foam. As the main support for the structure, the axially disposed wire will be subjected to the same forces as described for the unbonded wire, but the tendency of the wire to buckle is now restrained by foam matrix compressive resistance on the bowing side, and tensile forces on the opposite side between wire and foam because of the adhesive. Also, the circumferentially bonded adhesive on the wire itself will resist elongation and contraction of the wire's surface to provide additional stiffening and stability, further resisting the wire's tendency to buckle under compressive axial load.
It is therefore an object of the present invention to utilize the foam matrix itself, in combination with an adhesion to a fully encapsulated rigid sheet or membrane, for the prime purpose of laterally bracing said membrane to support high compressive axial load with minimum material expenditure. By volume, in the present invention the system is 88½% air, by which is created a structural matrix that laterally braces an axial-loaded membrane to produce ultimate strength. Therein, structural performance is maximized with minimum material.
It is a further object of the present invention to provide a high strength but extremely light weight axial load-bearing structural foamcore panel, where the strength to weight ratio can exceed 1000 to 1.
Another object of the present invention is to provide structural load-bearing wall panels wherein the encapsulated rigid sheet or membrane structure is in the form of longitudinally corrugated sheets with hollow tubular sections which are continuous across the entire dimension of the panels and establish a functionally homogeneous composite structure.
Yet another object of the present invention is to provide pairs of said corrugated sheets which, when reversed and mated together, form hollow tubular sections with perforated surfaces for the aspiration of process gases, the additional structural resistance against buckling, and the eventual installation of utilities related to panel erection in building construction.
Another object of the present invention is to p
Friedman Carl D.
Kile Bradford
Kile Goekjian Lerner & Reed PLLC
Yip Winnie
LandOfFree
Ultra-lite modular composite building system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ultra-lite modular composite building system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultra-lite modular composite building system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2867034