Hybrid insulating reinforced concrete system

Abstract

Hybrid Insulating Reinforced Concrete according to the present disclosure may be designed to create insulating reinforced concrete large-scale construction components for use in commercial, industrial and residential structures. Hybrid Insulating Reinforced Concrete meets those needs by providing an insulating reinforced concrete component that can either be: (1) cast-in-place at the job site, (2) pre-cast at a plant and shipped to the jobsite, or (3) a combination of the two techniques—utilize pre-cast insulating element trucked to the construction site and complete fabrication of the large-scale construction components on-site. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Description

RELATED APPLICATIONS

This application claims the priority of U.S. provisional application Ser. No. 60/487,156 filed Oct. 20, 2003.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to reinforced concrete construction components for use in commercial, industrial and residential structures and more specifically to large-scale reinforced insulating concrete construction components such as walls, decks, floors and roofs.

2. Description of the Prior Art

Reinforced concrete is a happy marriage between two complimentary materials, concrete and steel. The concrete supplies resistance to compressive loads, while the steel provides resistance to tensile loads. This in itself, however, would not make an effective long-term building material except for the fact that both concrete and steel have virtually the same coefficient of expansion. This means that in hot weather or in cold weather they expand or contract together—otherwise the bond between the two would be broken as they expanded or contracted at different rates, and it is the bond between the two materials that in the main makes reinforced concrete a useful building material.

In these days of rapidly increasing energy and land costs, there is a need for an insulating building material and/or system to provide less expensive means of construction and operation of the completed facility.

SUMMARY OF THE INVENTION

Concretes typically are made from a cementitious material, coarse and fine aggregates, water, and admixtures. Cement characteristics vary with regard to the fineness of the cementitious material, the rate at which they absorb water (hydrate) and their affinity for different admixtures which may be used to increase air entrainment, retard setting times and enhance other desired traits. Cementitious materials used in the formation of concrete include: Portland cement, fly-ash, silica fume, bentonite, and pozzolans (volcanic materials).

Aggregates vary from extremely hard and heavy natural aggregates; to soft and lightweight synthetic aggregates. For structural concrete, the main virtues of the resulting concrete is that its compressive strength can be tailored to the specific needs of the job, aggregate size and material can be varied dependent upon the required strength, placement techniques, and location of placement. For low-density non-structural concretes, the combination of cementitious materials, aggregates, and admixtures can be varied to meet the desired criteria for surface characteristics, surface roughness, and handling. In addition, aggregates can be selected for the thermal- and sound-resistive properties they bring to the concrete.

Initially, there seems to be little difference between the words “insulating concrete” and “insulated concrete”. However, there is a major difference between the two. Insulating concrete is concrete which in itself has distinct thermal and sound insulating properties. Insulated concrete is concrete upon which a layer of insulating material has been attached—(usually polystyrene or the like)—either sandwiched inside the component, attached outside on one side, or attached outside on both sides.

In a first aspect, Hybrid Insulating Reinforced Concrete according to the present disclosure is designed to create insulating reinforced concrete for large-scale construction components such as walls, floors, decking and roofs, for use in commercial, industrial and residential structures.

Hybrid Insulating Reinforced Concrete according to the present disclosure meets those needs by providing an insulating reinforced concrete component that can either be: (1) cast-in-place at the job site, (2) pre-cast at a plant and shipped to the jobsite, or (3) a combination of the two techniques—utilize pre-cast insulating element trucked to the construction site and complete fabrication of the large-scale construction components on-site. Structurally, large-scale construction components fabricated according to the present disclosure may be designed using the same design approach as for conventional reinforced concrete floor slab, deck, or wall—and the same sections of the building codes with the structural concrete portion of the component being designed to handle the required loads. For design purposes, the insulating concrete is not considered to contribute structurally. However, use of shaped insulating panels may reduce the amount of concrete required per component thereby decreasing the overall weight of a panel with concomitant savings in concrete and reinforcement while at the same time increasing thermal and sound insulating capacity.

A Hybrid Insulating Reinforced Concrete system according to the present disclosure consists of two main components: insulating concrete—with specific characteristics—and structural reinforced concrete. A Hybrid Insulating Reinforced Concrete system may be made from two different concretes, while other systems use non-cementitious polystyrene slabs or panels mechanically joined to the structural concrete. The insulating concrete provides several solutions for owners and contractors. First, the insulating concrete is designed to be lightweight in nature; have a four-hour fire rating as is—without coverings; be vermin, insect, and mold resistant; provide a readily finishable surface—not require furring strips; enable installation of electrical service within the wall surface; and increasing the sound and thermal insulating capacity to an otherwise typical reinforced concrete building component.

In another aspect, the present invention provides insulating concrete including:

• • Low-density and/ or light-weight aggregates
  • Admixtures to improve concrete handling characteristics and to enhance distribution of aggregates within cement matrix
  • Fibers and/or other reinforcement including steel wire mesh or deformed bar which may be used to enhance tensile nature of insulating concrete throughout the insulating concrete
  • Surface characteristics that allow for penetration of cement paste from wet structural concrete to create a uniform bond between the two materials.

and structural concrete including:

• • Normal or lightweight aggregate(s)
  • Optimized aggregate design
  • Admixtures to enhance setting characteristics
  • Reinforcement as required for flexure, shear, and deflection

In another aspect, Hybrid Insulating Reinforced Concrete system according to the present disclosure provides engineered surface characteristics of the insulating concrete. This low-density concrete is a material with large pore size and surface roughness. The engineered surface characteristics enables cement paste from the wet structural concrete to adhere, embed or otherwise engage the rough surface of the insulating concrete and form a continuous bond between the two surfaces. Consequently, a building component constructed according to the present disclosure does not require use of discrete mechanical connectors between the two materials. Additionally, as a concrete material itself, the insulating concrete provides the same thermal expansion as the structural concrete, and consequently continues to bond well to the structural concrete. This is another reason why discrete mechanical connectors between the insulating and structural concretes are not required.

In still another aspect, insulating concrete according to the present disclosure may be fabricated to provide the thickness desired for thermal or sound conditions. It may be precast into elements that may be Planar or Shaped 3 dimensional elements and subsequently transported to the construction site, or, the insulating concrete and the structural concrete may be cast-in-place at the construction site.

In still another aspect of the present disclosure, Planar and Shaped insulating elements, typically are rectangular, but may be molded or cut into other shapes as required. Shaped elements are designed to have one or both surfaces with cavities running in both length-wise and cross-wise directions. The cavities may be semi-circular or equivalently shaped. These elements are placed into formwork located upon a flat floor slab or the like with cavities aligned side-to-side and/or end-to-end to create large scale insulating panels upon with reinforcement may be laid and structural concrete is poured. large-scale building components can be fabricated in several ways:

• • 1. Cast the insulating concrete elements (Planar or Shaped) off-site, transport to construction area, lay said elements into pre-constructed formwork located on slab on grade or the like (coated with adequate releasing agent), bond or connect elements together to create a large-scale insulating panel, lay reinforcement, and pour structural concrete on top. Vibrate to ensure deposition of cement paste from wet structural concrete into pores of insulating concrete, and finish top surface.
  • 2. Cast the insulating concrete elements (Planar or Shaped) off-site, transport to construction area. Lay reinforcement in formwork, pour structural concrete, and set insulating concrete elements upon top surface of wet structural concrete and vibrate to ensure embedment of insulating concrete elements into upper surface of wet structural concrete. Strong-backs or the like may be used to position and hold insulating concrete elements in place. No mechanical connectors are required.
  • 3. Place wet insulating concrete into formwork to desired depth, let cure. Lay reinforcement on top, pour structural concrete and vibrate to ensure deposition of cement paste from wet structural concrete into pores of insulating concrete.
  • 4. Place wet insulating concrete into formwork to desired depth, let cure. Lay reinforcement on top, pour structural concrete, set a layer of pre-cast insulating concrete elements upon top surface of wet structural concrete and vibrate to ensure: (1) embedment of insulating concrete elements into upper surface of wet structural concrete and to ensure deposition of cement paste from wet structural concrete into bottom and top layers of insulating concrete.
  • 5. Place wet insulating concrete into formwork to desired depth, let cure. Lay reinforcement on top, pour structural concrete to desired depth and vibrate to ensure penetration of cement paste from wet structural concrete into bottom layer of insulating concrete. Upon still-wet structural concrete, pour a layer of insulating concrete, and let cure.

Lift points may be inserted into wet structural concrete as per conventional tilt-up or pre-cast construction methods and cured large-scale construction components lifted into place for floors, decks, walls, and/or roofs.

These and other features and advantages of this invention will become further apparent from the detailed description and accompanying figures that follow. In the figures and description, numerals indicate the various features of the invention, like numerals referring to like features throughout both the drawings and the description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a hybrid structural panel according to the present disclosure with one layer each of insulating and structural concrete.

FIG. 2 is a longitudinal cross-section of the device of FIG. 1.

FIG. 3, is an perspective view of Shaped hybrid panel according to the present disclosure.

FIG. 4 is a longitudinal cross-section of the device of FIG. 3.

FIG. 5 is a transverse cross-section of the device of FIG. 3.

FIG. 6 is a perspective view of an alternate embodiment hybrid structural panel according to the present disclosure with one interior layer of structural concrete and an exterior layer of insulating concrete on two opposing sides of the structural concrete layer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

For the purposes of the present disclosure, several definitions are necessary:

Element—the pre-cast insulating concrete shape.

Panel—when a number of the Elements are bonded or otherwise connected together they form a large-scale insulating concrete Panel—either Planar or Shaped.

Component—when the Panel and the reinforcement and structural concrete are all assembled together the result is a large-scale construction Component.

Insulating Concrete—an engineered low-density concrete with the same characteristics of expansion/contraction as structural concrete, with a sufficiently large pore size which enables cement paste from the wet structural concrete to become embedded within the surface of the insulating concrete thus forming a continuous bond between the two surfaces. Insulating Concrete resists heat and sound transmissions in particular.

Insulated Concrete—a structural or other type of concrete to which an insulating layer of polystyrene or the like has been affixed by means of extra mechanical and/or chemical (adhesive) connections.

Structural Concrete—as the name implies, the concrete that does the structural work resisting loads, flex, shear, deflection.

Referring now to FIG. 1, construction panel 2 includes structural concrete 6 bonded to insulating concrete 4. Insulating concrete 4 may include aggregate 4A which may be Low-density and/or light-weight materials such as expanded polystyrene, styrene beads, vermiculite, pumice, perlite, expanded shale, glass beads and/or other natural or man-made aggregates, and one or more admixtures 4B to improve concrete handling and strength characteristics and to enhance distribution of aggregate 4A within cement matrix 4M. Reinforcement 4F may include fibers, steel wire mesh or deformed bar or other suitable material may also be included to enhance tensile nature of insulating concrete 4 throughout construction panel 2.

Referring now to FIG. 2, in a longitudinal cross-section of construction panel 2, interface 10 may be examined in closer detail. Surface 12 of insulating concrete 4 has a surface roughness here identified as pores 14 to facilitate adhesion between insulating concrete 4 and structural concrete 6. Structural concrete 6 may also include reinforcing elements 8. In a currently preferred embodiment of the present disclosure, pores 14 may range in size up to ½″.

Mechanical interlocking of two concretes such as insulating concrete 4 and structural concrete 6 is due to the roughness or pores 14 of insulating concrete surface layer 5 of insulating concrete 4 and adsorption of cement paste from surface layer 13 of structural concrete 6 forming cement fingers 30.

Interlocking of surfaces such as insulating concrete surface layer 5 and structural concrete surface layer 13 can occur when:

• • the surface of the adherend is rough such as insulating concrete surface layer 5—this increases the area of physical contact; or
  • the interface between the two surfaces may contain “lock & key” sites such as pores 14 and cement fingers 30 respectively, or
  • penetration of cement paste from wet structural concrete 6 forms cement fingers 30 interlocking with pores 14 of insulating concrete 4.

Interface 10 is a suitable interlock between insulating concrete 4 and structural concrete 6 because Reduced stress concentration in interface 10 because adhesive properties of surface layer 13 and adherend insulating concrete surface layer 5 have similar physical parameters and little discontinuity exists in the physical properties. Similarly, adhesive surface layer 13 has a suitable viscosity/cure relationship.

Referring now to FIG. 3, in another embodiment of the present disclosure, construction panel 20 includes insulating concrete 22 and structural concrete 24. Insulating concrete 22 is formed to include horizontal cavities 26 and vertical cavities 27, although other suitable orientations of the cavities may be used. The combination of horizontal cavities 26 and vertical cavities 27 results in the formation of shaped elements 28. The shape of insulating concrete 22 provides greater surface area for better adhesion to structural concrete 24 and the inclusion of shaped elements 28 displaces concrete from structural concrete 24 thus lowering the weight of construction panel 20 and thus the installed cost.

Horizontal cavities 26 and vertical cavities 27 also provide structure for arranging reinforcing elements 8 as shown.

Referring now to FIG. 6, in an alternate embodiment of a hybrid insulating and reinforcing concrete panel according to the present disclosure, sandwich panel 2A includes structural concrete 6 between first insulating concrete 4A and second insulating concrete 4B.

Having now described the invention in accordance with the requirements of the patent statutes, those skilled in the art will understand how to make changes and modifications in the present invention to meet their specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention as set forth in the following claims.

Claims

1. A hybrid concrete panel comprising:

an insulating concrete panel having pores on a first surface; and

a reinforcing concrete panel forming cement fingers on a first surface, the cement fingers interlocking the pores of the first surface of the insulation concrete panel.

2. The hybrid concrete panel of claim 1 wherein the insulating concrete panel further comprises polystyrene.

3. The hybrid concrete panel of claim 1 wherein the reinforcing concrete panel further comprises a plurality of reinforcing elements.

4. The hybrid concrete panel of claim 1 wherein the insulating concrete panel and the reinforcing concrete panel are generally planar.

5. A hybrid concrete panel comprising:

a first insulating concrete panel having pores on a first surface;

a second insulating concrete panel having pores on a first surface; and

a reinforcing concrete panel forming cement fingers on a first surface and a second surface, the cement fingers of the first surface interlocking the pores of the first surface of the first insulating concrete panel, and the cement fingers of the second surface interlocking the pores of the first surface of the second insulating concrete panel.

6. The hybrid concrete panel of claim 5 wherein the first and second insulating concrete panels and the reinforcing concrete panel are generally planar.