Static structures (e.g. – buildings) – With synthetic resinous component – With nonresinous component
Reexamination Certificate
1999-05-28
2001-02-06
Kent, Christopher T. (Department: 3635)
Static structures (e.g., buildings)
With synthetic resinous component
With nonresinous component
C052S309800, C052S309140, C052S309150, C052S309170, C052S284000, C052S592100, C052S794100, C052S783100, C052S783130, C052S749100, C052S749100, C052S749100
Reexamination Certificate
active
06182409
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a building element.
BACKGROUND TO THE INVENTION
There is a need for a light weight building element which in its own right has structural integrity and which can be coupled with other such light building elements for the purposes of building panels, walls and various structural components in the formation of buildings.
It is an important consideration that such structural elements have significant strength and should have a reasonably high resistance to fire.
Classically in order to provide both the compressive strength and the tensile strength required of building elements, steel reinforcement (which has tensile strength) has been provided within concrete (which has compressive strength). However the resulting elements, because of the density of the concrete, have been heavy and not readily manipulable when manufactured in the form of prefabricated panels, columns and the like.
This problem of the weight of composite steel in concrete structures is not solved by using a low density material such as aerated concrete to carry the compressive loads. This is because steel-reinforced concrete relies on bonding between the concrete and the steel reinforcing. This bonding effect is not possible with aerated concrete. The light weight of aerated concrete is achieved by the presence of air pockets within the bulk of the concrete. The presence of these air pockets results in a lower steel to concrete bonding area, and far less effective bonding. There are similar difficulties in obtaining adhesion or bonding between reinforcing steel and other light weight alternatives to conventional concrete.
SUMMARY OF THE INVENTION
The present invention provides:
a building element comprising an outer sheath and an inner core, and being able to carry either or both of tensile loadings and compressive loadings without adhesion between the outer sheath and the inner core,
the sheath being formed of a material having a greater tensile strength than compressive strength;
and the core being formed of a material having:
a greater compressive strength than tensile strength; and
a density of less than 1,200 kg/cu meter;
wherein the outer sheath is longitudinally extending and has a first face and a second face which are spaced apart, first and second edges and a first end and a second end,
wherein the first face and the second face are joined at the first and second edges to form the outer sheath as a continuous body, and
wherein the first edge and the second edge are so shaped that the first edge of one such building element is adapted to locate in the second edge of another such building element.
PREFERRED ASPECTS OF THE INVENTION
Preferably the first end and the second end are so shaped that the first end of one such building element is adapted to engage with the second end of another such building element.
However, plain ends may be acceptable in some instances.
Preferably the sheath comprises at least two components which can interengage with one another to form the sheath. In one instance the sheath comprises four components.
In the last instance, two components define the faces and two components define the edges.
A plurality of such building elements may be assembled edge to edge to form walls, floors, roof, cladding or other parts of a building.
The building elements may extend horizontally, vertically or as desired.
The material of which the sheath is formed need only satisfy the tensile strength requirement.
Suitable materials for the sheath include mild steel, high tensile steel, carbon fibre materials, extruded materials, synthetic plastic-cement fibre composite and asbestos cement or modem replacement therefor.
The material of which the core is formed need only satisfy the compressive strength requirement.
However, the material of the core desirably has a substantially higher resistance to fire than the material of the sheath.
The preferred material of the core is a cementitious material. An alternative core material is a non-fire resistant material of low density, displaying a degree of compression resistance. Foamed plastics, eg polystyrene, and other materials such as recycled paper and recycled plastics may be used.
A most preferred cementitious material is a light weight concrete.
One suitable concrete is aerated concrete. Aerated concrete has a density of 200-1200 kg/cu meter, and although it is referred to in the art as ‘concrete’ is not strictly concrete because it does not contain aggregate.
Desirably, the spacing between the first edge and the second edge does not exceed 450 mm with 200-300 mm being preferred.
The spacing between the first and the second faces depends on the design loads for the building element. These edges may be closely spaced, and as a practical matter their maximum spacing is unlikely to exceed
150
mm, depending on the application.
Preferably the first face and the second face and/or the first edge and the second edge are joined by at least one web located intermediate of the edges.
Said at least one web is preferably apertured.
This last has a number of advantages including that the amount of material in the web is reduced, so that the core material on one side of the web is integrally connected to the core material on the other side of the web, so as to reduce the amount of material available for heat conduction, as a stabiliser in manufacturing and to provide a continuous tensile shell enabling point stress loads to transfer to the outer sheath.
Several such webs may be used.
The length of the building element is not critical but for practical purposes is unlikely to exceed 8 meters.
In a preferred aspect the present invention provides a building element comprising an outer sheath and an inner core, and being able to carry either or both of tensile loadings and compressive loadings without adhesion between the outer sheath and the inner core,
the sheath being formed of a material having a greater tensile strength than compressive strength;
and the core being formed of a material having:
a greater compressive strength than tensile strength; and
a density of less than 1,200 kg/cu meter;
wherein the first edge and the second edge are so shaped that the first edge of one such building element is adapted to locate in the second edge of another such building element and wherein,
when so located, the core material of said one such panel is spaced not more than 3 mm from the core material of said another panel.
Preferably that spacing of the core material of said one panel and the core material of said another panel does not exceed 1 mm.
Preferably the first edge defines a tongue and the second edge defines a groove.
Preferably the core material extends into the tongue.
The core material may extend into the portion of the sheath defining the groove but this is not preferred.
Preferably the groove is of such depth as to overly the first and second faces of such a building element when the tongue is entered into the groove of another such building element.
Preferably the building element, in the region of the groove, has a groove width, measured between the first face and the second face, of about the spacing of the first face and second face less four times the thickness of the sheath material.
Specific embodiments of building elements in accordance with this invention as applied to building panels will now be described by way of non-limiting example with reference to the accompanying drawings.
REFERENCES:
patent: 3913292 (1975-10-01), Braekkan
patent: 4774794 (1988-10-01), Grieb
patent: 5115621 (1992-05-01), Kobayashi
patent: 5664386 (1997-09-01), Palmersten
patent: 5765318 (1998-06-01), Michelsen
patent: 5842314 (1998-12-01), Porter
patent: 5927032 (1999-07-01), Record
patent: 6006480 (1999-12-01), Rook
patent: 6096416 (2000-08-01), Altenberg
patent: 229435 (1992-12-01), None
Kent Christopher T.
Milde Hoffberg & Macklin, LLP
Thissell Jennifer I.
LandOfFree
Building element does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Building element, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Building element will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2588201