US20090313926A1

US20090313926A1 - Connection for sandwich panel and foundation

Info

Publication number: US20090313926A1
Application number: US12/142,865
Authority: US
Inventors: Ulrich SCHWARTAU
Original assignee: Innovida Factories Ltd
Current assignee: MILLPORT ASSOCIATES SA
Priority date: 2008-06-20
Filing date: 2008-06-20
Publication date: 2009-12-24

Abstract

A joint connecting a sandwich panel to a foundation comprising, a sandwich panel having a core and two outer layers separated from one another by the core, an anchor in the foundation, a U-shape member having two side walls and a bottom wall extending between the sidewalls, the bottom wall defining a opening that is aligned with the anchor in the foundation and a securing member insertable through the opening in the bottom wall of the U-shape member and engaged to the anchor to secure the U-shape member to the anchor, wherein the U-shape member is connected to the outer layers of the sandwich panel by bonding material between the outer layers of the sandwich panel and the side walls of the U-shape member.

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to constructing buildings, and more particularly, to a joint and method of connecting a sandwich panel to a building foundation.

DESCRIPTION OF THE RELATED ART

There is an increasing global demand for lower cost buildings such as houses, warehouses and office space. The demand for lower cost buildings is particularly strong in developing countries where economic resources may be limited and natural resources and raw materials may be scarce. For example, in areas of the Middle East or Africa, conventional building materials such as cement, brick, wood or steel may not be readily available or, if available, may be very expensive. In other areas of the world, poverty may make it too costly for people to build houses or other buildings with conventional materials.
The demand for lower cost housing also is high in areas afflicted by war or natural disasters, such as hurricanes, tornados, floods, and the like. These devastating events often lead to widespread destruction of large numbers of buildings and houses, especially when they occur in densely populated regions. The rebuilding of areas affected by these events can cause substantial strain on the supply chain for raw materials, making them difficult or even impossible to obtain. Furthermore, natural disasters often recur and affect the same areas. If a destroyed building is rebuilt using the same conventional materials, it stands to reason that the building may be destroyed or damaged again during a similar event.
It is generally desirable to increase speed of construction and to minimize construction costs. Prefabricated or preassembled components can streamline production and reduce both the time and the cost of building construction. Prefabricated buildings, however, are made from conventional materials that may be scarce or expensive to obtain. Thus, there exists a need for alternative materials and techniques for constructing buildings that use advanced material technologies to increase the speed of construction and to reduce or to lower ownership costs.

SUMMARY

The present invention provides an alternative to conventional construction materials and techniques. Buildings, such as houses, commercial buildings, warehouses, or other structures can be constructed by composite sandwich panels (also referred to as “sandwich panels” or “composite panels”), which have an insulative core and one or more outer layers. The buildings can be constructed by gluing several sandwich panels together, and usually traditional fasteners, such as screws, rivets, nails, etc., are not needed for such connections. Generally, composite sandwich panels offer a greater strength-to-weight ratio than traditional materials that are used by the building industry. The composite sandwich panels are generally as strong as, or stronger than, traditional materials including wood-based and steel-based structural insulation panels, while being lighter in weight. Because they weigh less than traditional building materials, the handling and transport of composite sandwich panels is generally less expensive. The composite sandwich panels also can be used to produce light-weight buildings, such as floating houses or other light-weight structures.
Sandwich panels generally are more elastic or flexible than conventional materials such as wood, concrete, steel or brick and, therefore, monolithic (e.g., unitary or single unit structure) buildings made from sandwich panels are more durable than buildings made from conventional materials. For example, sandwich panels also may be non-flammable, waterproof, very strong and durable, and in some cases able to resist hurricane-force winds (up to 300 Kph (kilometers per hour) or more). The sandwich panels also may be resistant to the detrimental effects of algae, fungicides, water, and osmosis. As a result, buildings constructed from sandwich panels may be better able to withstand earthquakes, floods, tornados, hurricanes, fires and other natural disasters than buildings constructed from conventional materials.
A number of construction elements, e.g., one or more composite sandwich panels, can be connected together to construct a building. For example, the sandwich panels may be connected to build and erect walls, to build ceilings or roofs, or to divide the interior of the building into one or more rooms, etc. The building may be constructed on a foundation, for example, a foundation that is formed from a generally rigid material, such as concrete. As described in more detail below, the sandwich panels may be connected to the foundation with a joint that includes bonding material and a number of rigid members or securing members engaged to the foundation.
According to one embodiment of the invention, a joint connecting a sandwich panel to a foundation including a sandwich panel having a core and two outer layers separated from one another by the core, an anchor in the foundation, a U-shape member having two side walls and a bottom wall extending between the sidewalls, the bottom wall defining a opening that is aligned with the anchor in the foundation, and a securing member insertable through the opening in the bottom wall of the U-shape member and engaged to the anchor to secure the U-shape member to the anchor, wherein the U-shape member is connected to the outer layers of the sandwich panel by bonding material between the outer layers of the sandwich panel and the side walls of the U-shape member.
According to one aspect, the joint includes bonding material between bottom wall of U-shape member and the foundation.
According to another aspect of the joint, the securing member includes a bolt and a washer, wherein the washer is disposed between a head of the bolt and the bottom wall of the U-shape member.
According to another aspect of the joint, the securing member includes at least one of a bolt, screw, washer or nut.
According to another aspect, the joint further includes at least one additional securing member and anchor, wherein the additional securing member is insertable through a second opening in the bottom wall of the U-shape member and secured to a second anchor in the foundation.
According to another embodiment of the invention, a method of joining a sandwich panel to a foundation with a U-shape member, wherein the U-shape member includes a bottom wall and two side walls connected to one another by the bottom wall, the bottom wall having a opening defined by the bottom wall, the method including: setting an anchor into a foundation, connecting the U-shape member to the foundation with bonding material, inserting a securing member through the opening in the bottom wall of the U-shape member and engaging the securing member to the anchor to secure the U-shape member to the foundation; inserting an edge portion of a sandwich panel into the U-shape member; and connecting the sandwich panel to the U-shape member with bonding material.
According to another aspect, the method further includes placing a washer between a head of the securing member and the bottom wall of the U-shape member.
According to another aspect, the method further includes inserting a second securing member through a second opening in the bottom wall of the U-shape member and engaging the additional securing member to an additional anchor.
According to another aspect of the method the step of connecting the U-shape member to the foundation includes applying bonding material between the outer layers of the sandwich panel and the side walls of the U-shape member.
According to another embodiment, a joint connecting a sandwich panel to a foundation member, the joint including: a wall comprised of at least one sandwich panel having a core and two outer layers separated from one another by the core; a U-shape member extending along an edge of the wall, the U-shape member having a bottom wall and two side walls connected to one another by the bottom wall, wherein each of the side walls of the U-shape member are connected to respective outer layers of the wall, and wherein the bottom wall of the U-shape member includes a opening; a foundation member; at least one anchor set in the foundation member; and at least one connection between the U-shape member and the foundation, wherein the connection is comprised of a bolt inserted through the opening in the bottom wall of the U-shape member and engaged to the anchor and bonding material between the bottom wall of the U-shape member and the foundation member.
According to one aspect of the joint, the bottom wall of the U-shape member includes a second opening, and wherein the connection further comprises a second bolt inserted through the second opening and engaged to a second anchor in the foundation.
According to another aspect of the joint, the U-shape member further includes a number of openings in the bottom wall, and the connection between the U-shape member and the foundation further comprises, a number of bolts inserted through the openings in the bottom wall of the U-shape member and engaged to a number of anchors in the foundation.
According to another embodiment, a method of building construction, including attaching a U-shape member to a building foundation, placing an edge portion of a sandwich panel in the U-shape member, and bonding the edge portion to the U-shape member.
According to one aspect of the method, the attaching includes using a rigid member attached to the building foundation and securing the rigid member to the U-shape member.
According to another aspect of the method, the attaching includes placing a bonding material between the building foundation and the generally U-shape member.
According to another aspect of the method, the bonding includes applying a bonding material between side walls of the sandwich panel and side walls of the generally U-shape member.
According to another aspect, the method further includes using the sandwich panel as a wall of the building.
According to another aspect of the method, the sandwich panel includes a relatively easily deformable portion sandwiched between respective relatively non-deformable outer layers, wherein said attaching comprises using a relatively rigid member having an end exposed to the relatively easily deformable portion of the sandwich panel, and pressing the sandwich panel against such rigid member end to cause such end portion of the sandwich panel to at least partially envelop such rigid member end.
According to another aspect, the method further includes applying bonding material between the end/edge of the sandwich panel and the bridge portion of the generally U-shape member.
These and further features of the present invention will be apparent with reference to the following description and attached drawings. In the description and drawings, particular embodiments of the invention have been disclosed in detail as being indicative of some of the ways in which the principles of the invention may be employed, but it is understood that the invention is not limited correspondingly in scope. Rather, the invention includes all changes, modifications and equivalents coming within the spirit and terms of the claims appended hereto.
It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with, or instead of, the features of the other embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an environmental view of an exemplary monolithic structure built with composite materials on a foundation.

FIG. 2 is a cross-sectional view of a joint between a sandwich panel and the foundation generally along the lines 2-2 of FIG. 1.

FIG. 3 is a front view of a joint between a sandwich panel and the foundation.

FIG. 4 is an isometric view of an exemplary sandwich panel.

DETAILED DESCRIPTION OF EMBODIMENTS

In the detailed description that follows, like components have been given the same reference numerals regardless of whether they are shown in different embodiments of the invention. To illustrate the present invention in a clear and concise manner, the drawings may not necessarily be to scale and certain features may be shown in somewhat schematic form. Certain terminology is used herein to describe the different embodiments of the invention. Such terminology is used for convenience when referring to the figures. For example, “upward,” “downward,” “above,” “below,” “left,” or “right” merely describe directions in the configurations shown in the figures. Similarly, the terms “interior” and exterior” or “inner” and “outer” may be used for convenience to describe the orientation of the components in the figures. The components can be oriented in any direction and the terminology should therefore be interpreted to include such variations. The dimensions provided herein are exemplary in nature and are not intended to be limiting in scope. Furthermore, while described primarily with respect to house construction, it will be appreciated that the concepts described herein are equally applicable to the construction of any type of structure or building, such as warehouses, commercial buildings, factories, apartments, etc.
The structures described herein are built with composite materials, such as composite sandwich panels. The sandwich panels may be formed from synthetic or natural materials and may provide a light-weight and potentially less expensive alternative to conventional raw materials, e.g., wood, concrete, metal, etc. The sandwich panels may be connected or joined together with a high-strength bonding material, such as epoxy or glue. The result is a strong and durable monolithic structure, as is described further below.
Referring to FIG. 1, an exemplary monolithic structure 10, for example, a house, is built from a number of sandwich panels that are connected together with bonding material. The house 10 includes a front wall 10 f formed by connecting together sandwich panels 11, 12, 13, 14, a side wall 10 s formed by connecting together sandwich panels 15, 16 together, and a roof 17 connected to the walls 10 s, 10 f. The house 10 also may include a number of openings 18, which may be used to install doors or windows. The front wall 10 f and side wall 10 s are connected to one another at a corner 10 c of the house 10. Although not shown in FIG. 1, it will be appreciated that the house 10 may include a number of other walls connected together, e.g., another side wall, a rear wall, internal walls, etc., and may include multiple levels.
As is shown in FIGS. 1 and 2, the house 10 is constructed on a foundation 20, for example, a concrete foundation. The walls, e.g., walls 10 f, 10 s, of the house 10 are connected to the foundation 20 by a joint 21. The joint 21 includes a joining mechanism 22, for example, a generally U-shape member, connected to the foundation 20 with bonding material 23, a rigid member 24 (also referred to as a “securing member”), and an anchor 25. The rigid member 24 and the anchor 25 form a connection 26 a between the U-shape member 22 and the foundation 20 as is shown in more detail in FIG. 2. The U-shape member 22 is connected to a sandwich panel, e.g., sandwich panel 12, by bonding material 30, 31. As shown by dashed lines in FIG. 1, the joint 21 may include a number of connections, several of which are shown at 26 a-26 f, along the length of the walls of the house 10.
Continuing to refer to FIGS. 1-2, the foundation 20 has a generally planar or horizontal surface 32 on which the house 10 is constructed. The foundation 20 may be anchored or embedded into the ground and should be thick enough and have sufficient strength and rigidity to support the weight of the house 10. The thickness of the foundation 20 may be determined or may be calculated by an engineer or architect.
The foundation 20 may be constructed or formed by a generally rigid material. For example, the foundation 20 may be poured from concrete, or the foundation 20 may be made from one or more composite sandwich panels, steel, wood, a concrete slab, etc. The foundation 20 may be poured into a trench. The foundation may be a slab, one or more courses of brick, or may be another type of foundation. To facilitate the description herein, the foundation 20 will be referred to as a concrete foundation, however, it will be appreciated that the description is equally applicable to a foundation formed from other materials.
FIG. 2 is a sectional view looking generally in the direction along the lines 2-2 of FIG. 1 showing the details of an exemplary connection 26 a between the rigid member 24 and anchor 25. As shown in FIG. 2, the joint 21 includes U-shape member 22, bonding material 23, a rigid member 24 and an anchor 25. The other connections 26 b-26 f may be the same as or similar to the connection 26 a.
The U-shape member 22 has two upstanding members 33, 34 (also referred to as side walls) and a bridge portion 35 (also referred to as a “bottom wall”), which extends between the upstanding members 33, 34. The side walls 33, 34 and the bottom wall 35 form the general shape of a “U”. The U-shape member 22 may be formed from composite materials, for example, the composite materials used to construct the outer layers of a sandwich panel 12, which are described in more detail with respect to FIG. 4. The side walls 33, 34 and bottom wall 35 may be relatively thin with respect to the sandwich panel 12. In one embodiment, the walls 33, 34, 35 are several millimeters thick and may be, for example between about 1-12 mm (millimeters) thick; however, it will be appreciated that the walls can be thinner than 1 mm (millimeter) or thicker than 12 mm (millimeters) as may be desired.
The U-shape member 22 is connected to surface 32 of the foundation 20 by bonding material 23. The U-shape member 22 is connected to the sandwich panel 12 by bonding material 30, 31. The bonding material 23, 30, 31 may be any suitable bonding material such as epoxy, epoxy resin, glue, cement, adhesive, adhering material or another bonding material (these terms may be used interchangeably and equivalently herein).
The bottom wall 35 of the U-shape member 22 and the surface 32 of the foundation 20 may be uneven, for example, due to variations during the manufacturing process. The unevenness in surfaces may cause gaps between the bottom wall 35 of the U-shape member 22 and the surface 32 of the foundation 20. To eliminate or to close the gaps, the bonding material 23 is applied as a layer between the U-shape member 22 and the surface 32. The layer of bonding material 23 may be applied before the U-shape member 22 is placed on the foundation 20. The U-shape member 22 may be pressed into the layer of bonding material 23 to force any pockets of air from the space between the U-shape member 22 and the surface 32 thereby forming a continuous joint 21. The bonding material 23 seals the joint 21 and may prevent or block fluid or debris from entering the joint and/or damaging the connection between the U-shape member 22 and the foundation 20. The bonding material 23, therefore, compensates for any unevenness in the bottom wall 35 of the U-shape member 22 and the foundation 20 and also seals the joint 21. The bonding material 23 also facilitates the transmission of forces or loads between the sandwich panel 12, securing member 24, the U-shape member 22, and the foundation 20. The bonding material 23 also secures the U-shape member 22 and the sandwich panel 12 to the foundation 20, for example, in the event that the sandwich panel 12 is subjected to forces or loads that are perpendicular or normal to the outer layers (e.g., outer layer 41 or 42).
In one embodiment, the layer of bonding material 23 may be about 2-4 cm (centimeters) thick. In another embodiment, the layer of bonding material 23 is no more than about 2 cm (centimeters) thick. It will be appreciated that thicker or thinner layers of bonding material 23 may be used, as may be desired.
The bottom wall 35 of the U-shape member 22 includes an opening 36, for example, a hole or a slot, which is defined by or is provided in the bottom wall 35. The opening 36 is aligned with the anchor 25 when the U-shape member 22 is connected to the foundation 20. The opening 36 provides a pathway or hole through which the rigid member 24 is inserted to connect the U-shape member 22 to the foundation 20. The opening 36 may be a circular shape or may be another shape, such an oblong or elongate shape to facilitate alignment of the opening 36 with the anchor 25. The opening 36 may be formed by punching, cutting, drilling or otherwise removing a portion of the bottom wall 35. The opening 36 may be formed during the manufacturing process or may be formed at the construction site.
The rigid member or securing member 24 may include a threaded portion 24 a and a head 24 b. The securing member 24 is insertable through the opening 36 to engage the anchor 25 to secure or to connect the U-shape member 22 to the foundation 20. In one embodiment, the securing member 22 is a bolt. The size of the bolt may be selected based upon several variables, such as the size of the U-shape member 22, the size of the wall that is connected to the U-shape member, and the number of connections between the U-shape member and the foundation. In one embodiment, the bolt is a M8×60 bolt (e.g. ISO 1891) that engages an anchor 25 having a corresponding M8 thread. It will be appreciated that the securing member may be a different size. It also will be appreciated that the securing member 24 may be one or more screw, nail, rivet or other member that may engage the anchor 25 in the foundation to secure the U-shape member 22 to the foundation 20.
The anchor 25 is set, fixed, or embedded in the foundation 20. The anchor 25 may be an expansion-type concrete anchor having a threaded portion 25 a for mating with the securing member 24. The anchor 25 may be connected to the foundation 20 by drilling a hole in the surface 32 of the foundation 20. The anchor 25 may be placed in the hole and secured to the foundation 20 by engaging the threads 24 a of the securing member 24 to the threads 25 a of the anchor 25, which causes the anchor 25 to expand and contact the sides of the holes in the foundation 20. The expansion of the anchor 25 creates a compression fit between the anchor 25 and the foundation 20 and fixes or secures the anchor 25 the foundation 20 in a relatively permanent manner. The anchor 25 may be suitable for use with concrete. In one embodiment, the anchor 25 has M8 threads that mate with an M8 bolt.
It will be appreciated that other masonry-type anchors may be used, such as, for example, concrete screws, hammer anchors, one-piece expansion anchors and two-step expansion anchors, etc. Rather than drilling a hole in the foundation 20, the anchor 25 may be set in the foundation 20 while the concrete is wet and/or moldable. The anchor 25 may be secured to the foundation 20 with bonding material or another adhesive. As will be appreciated, the size of the anchor 25 may be selected based upon the magnitude of the forces, loads, or stresses that the anchor is expected to support, for example, the anticipated or calculated shear loads and/or tensile loads.
The joint 21 also includes a washer 40. The washer 40 may be placed between the head 24 b of the securing member 24 and the bottom wall 35 of the U-shape member 22. The washer 40 facilitates the transfer, distribution, and/or spreading of loads or forces from the securing member 24 to the U-shape member 22 and the sandwich panel 12.
The securing member 24 is connected to the anchor 25 by engaging the threads 24 a of the securing member 24 with the threads 25 a of the anchor 25. The securing member 24 is tightened to fixedly secure the U-shape member to the foundation 20. As the securing member 24 is tightened, the head 24 b engages the washer 40, and the washer 40 is pressed into contact with the bottom wall 35 of the U-shape member 22. The securing member 24, therefore, creates compressive forces between the head 24 b and the U-shape member 22. The forces are distributed over an area and spread to the bottom wall 35 of the U-shape member 22 by the washer 40.
The size of the washer 40 may be selected based upon the size of the U-shape member 22. A sufficient tolerance or space should be maintained between the side walls 33, 34 and the washer 40 to avoid rubbing the washer 40 against the side walls 33, 34, for example, during natural expansion and/or contraction of the walls due to heat or from wind or other forces acting on the walls of the house 10. The washer 40 generally should have a small enough diameter to avoid or to minimize rubbing or other contact with the side walls 33, 34 of the U-shape member 22. The washer 40 also should be large enough to provide a sufficient surface for distributing loads or forces acting on the walls to the foundation 20. For a sandwich panel 12 that is about 60 mm (millimeters) in diameter, the washer 40 may have a diameter between about 50 mm (millimeters)-55 mm (millimeters). It will be appreciated that diameter of the washer 40 may be larger for wider sandwich panels or the diameter of the washer 40 may be smaller for narrower sandwich panels.
It will be appreciated that other configurations of the securing member 24 and anchor 25 are possible. For example, the securing member 24 may be a screw or bolt that is embedded in the foundation 20 and that has a threaded portion that extends outwardly from the surface 32. The threaded portion of the screw or bolt may be inserted through the opening 36 in the bottom wall 35 of the U-shape member 22. The screw or bolt may be engaged to a washer and a nut. The nut with the washer may be tightened against the bottom wall 35 of the U-shape member 22 to secure the U-shape member 22 to the foundation 20.
As mentioned above, the U-shape member 22 is connected or bonded to the sandwich panel 12. The sandwich panel 12, which is described in more detail with respect to FIG. 4, includes two outer layers 41, 42 separated by a core 43. The sandwich panel 12 has an edge 44 near or in contact with the bottom wall 35 of the U-shape member 22. The U-shape member 22 is connected to the sandwich panel 12 near the edge 44 by bonding material 30, 31 between the side walls 33, 34 of the U-shape member 22 and the outer layers 41, 42 of the sandwich panel 12.
As shown in FIG. 2, the edge 44 of the sandwich panel 12 may be separated or spaced from the bottom wall 35 by a gap 45. The edge 44 may abut or contact the head 24 b of the securing member 24. The edge 44 may be pressed against the U-shape member 22 and may be pressed against the bottom wall 35. The panel core 43, which may be formed from a compressible or deformable material, for example, a foam material, is sandwiched between two relatively non-deformable members e.g., outer layers 40, 41. The deformable panel core 43 may be compressed around the head 24 b of the securing member 24, such that the securing member 24 is at least partially embedded or enveloped by the panel core 43. The panel core 43 also may be compressed around the washer 40, such that the edge 44 is in contact with the bottom wall 35 of the U-shape member 22. Bonding material may be spread or applied at the edge 44 to close or seal the core 43.
Referring to FIG. 3, two illustrative connections 26 a, 26 b between the securing member 24 and the anchor 25 are shown. The joint 21 may include a number of connections, e.g., connections 26 a-26 f (FIG. 1). As described above with regard to the connections 26 a in the discussion of FIG. 2 above, the connections 26 a, 26 b include a securing member 24, an anchor 25 and a washer 40. The connections 26 a, 26 b are spaced from one another a distance A. The distance A between the securing members 21 a, 21 b may be based upon the size of the anchors 25 and the anticipated forces that the anchors 25 may cause in the foundation 20 as a result of being fixed in the foundation 20.
The connections 26 a, 26 b should be close enough to one another to provide adequate support to the U-shape member 22 and to withstand the forces that may be transferred or transmitted between the sandwich panel 12, the securing member 24 and/or the foundation 20. The connections 26 a, 26 b also should be spaced a minimum distance A to avoid cracking the foundation. For example, if the anchors 25 are expansion-type anchors, forces will be created in the foundation 20 when that securing members 24 are tightened to the anchors 25, causing the anchors 25 to expand. If the anchors 25 are too close to one another, the foundation 20 may crack between the anchors.
In one embodiment, the distance A between the securing members 21 a, 21 b is about 100 cm (centimeters)-120 cm (centimeters). In another embodiment, the distance A between the connections 26 a, 26 b is at least about 100 cm (centimeters). It will be appreciated that the connections 26 a, 26 b may be closer or farther apart based upon the rigidity and/or durability of the foundation 20, the materials used to construct the foundation 20, the anticipated loads that the U-shape member 22 may need to support, etc.
Although illustrated in FIG. 3 as having two connections 26 a, 26 b, it will be appreciated that the house 10 may have additional connections, such as, for example, connections 26 c-26 f at the front wall 10 f and/or side wall 10 s of the house 10. Additional connections also may be located along other walls of the house 10.
The house 10 (or other building) is constructed by attaching a joining mechanism, e.g., the connection 26 a, to the building foundation 20 and a sandwich panel, e.g., sandwich panel 12. The sandwich panel 12 may be installed or erected as part of a wall (e.g., wall 10 f or wall 10 s) of a building 10. The sandwich panel 12 includes a relatively easily deformable portion 43 or core sandwiched between respective relatively non-deformable outer layers 41, 42.
The connection 26 a includes the generally U-shape member 22 connected to the sandwich panel 12 by inserting an edge or end portion 44 of the sandwich panel into the U-shape member 22. Bonding material 30, 31 is applied between the side walls 33, 34 of the U-shape member 22 and the outer layers 41, 42 of the sandwich panel 12. Additional bonding material may be applied between the sandwich panel edge 44 and the bottom wall or bridge portion 35 of the U-shape member 22.
The U-shape member 22 also is connected to the foundation by spreading or applying bonding material 23 between the building foundation 20 and the U-shape member 22, as described above with respect to FIG. 2.
A rigid member, e.g., the securing member 24, is secured to the building foundation 20 and to the U-shape member 22. The rigid member has an end 25 a that is engaged to the anchor 25 in the foundation 20 and another end 24 s, which is inside the U-shape member 22. When attaching the sandwich panel 12 to the foundation 20, the end 24 a of the rigid member 24 is exposed to the relatively easily deformable portion 43 of the sandwich panel 12. The end 24 a of the rigid member 24 is pressed into the deformable portion 43 of the sandwich panel 12 by pressing the edge 44 of the sandwich panel 12 against the end 24 a of the rigid member 24 to at least partially envelop the end 24 a.
As will be appreciated, additional steps for connecting the sandwich panel 12 to the foundation 20 with the U-shape member 22 and rigid member 24 may be involved according to the structures described above with respect to FIGS. 1-3.
Referring now to FIG. 4, a sandwich panel is shown in more detail. The sandwich panel 12 includes two outer layers 41, 42 separated by a core 43. The outer layers 41, 42 are bonded or adhered to the core 43 with bonding material.
The core 43 of the exemplary sandwich panel 12 may be formed from a light-weight, insulative material, for example, polyurethane, expanded polystyrene, polystyrene hard foam, Styrofoam® material, phenol foam, a natural foam, for example, foams made from cellulose materials, such as a cellulosic corn-based foam, or a combination of several different materials. Other exemplary core materials include honeycomb that can be made of polypropylene, non-flammable impregnated paper or other composite materials. It will be appreciated that these materials insulate the interior of the structure and also reduce the sound or noise transmitted through the panels. The core may be any desired thickness and may be, for example, about 30 mm (millimeters)-100 mm (millimeters) thick, however, it will be appreciated that the core can be thinner than 30 mm (millimeters) or thicker than 100 mm (millimeters) as may be desired. In one embodiment, the core is about 60 mm (millimeters) thick.
The outer layers 41, 42 of the sandwich panel 12, are made from a composite material that includes a matrix material and a filler or reinforcement material. Exemplary matrix materials include a resin or mixture of resins, e.g., epoxy resin, polyester resin, vinyl ester resin, natural (or non oil-based) resin or phenolic resin, etc. Exemplary filler or reinforcement materials include fiberglass, glass fabric, carbon fiber, or aramid fiber, etc. Other filler or reinforcement materials include, for example, one or more natural fibers, such as, jute, coco, hemp, or elephant grass, balsa wood, or bamboo.
The outer layers 41, 42 (also referred to as laminate) may be relatively thin with respect to the panel core 43. The outer layers 41, 42 may be several millimeters thick and may, be, for example between about 1 mm (millimeter)-12 mm (millimeters) thick, however, it will be appreciated that the outer layers can be thinner than 1 mm (millimeter) or thicker than 12 mm (millimeters) as may be desired. In one embodiment, the outer layers are about 1-3 mm (millimeter) thick.
It will be appreciated that the outer layers 41, 42 may be made thicker by layering several layers of reinforcement material on top of one another. The thickness of the reinforcement material also may be varied to obtain thicker outer layers 41, 42 with a single layer of reinforcement material. Further, different reinforcement materials may be thicker than others and may be selected based upon the desired thickness of the outer layers.
The outer layers 41, 42 are adhered to the core 43 with the matrix materials, such as a resin mixture. Once cured, the outer layers 41, 42 of the sandwich panel 12 are firmly adhered to both sides of the panel core 43, forming a rigid building element. It will be appreciated that the resin mixture also may include additional agents, such as, for example, flame retardants, mold suppressants, curing agents, hardeners, etc. Coatings may be applied to the outer layers 41, 42, such as, for example, finish coats, paint, ultraviolet (UV) protectants, water protectants, etc.
The core 43 may provide good thermal insulation properties and structural properties. The outer layers 41, 42 may add to those properties of the core and also may protect the core 43 from damage. The outer layers 41, 42 also provide rigidity and support to the sandwich panel.
The sandwich panels may be any shape. In one embodiment, the sandwich panels are rectangular in shape and may be several meters, or more, in height and width. The sandwich panels also may be other shapes and sizes. The combination of the core 43 and outer layers 41, 42 create sandwich panels with high ultimate strength, which is the maximum stress the panels can withstand, and high tensile strength, which is the maximum amount of tensile stress that the panels can withstand before failure. The compressive strength of the panels is such that the panels may be used as both load bearing and non-load bearing walls. In one embodiment, the panels have a load capacity of at least 50 tons per square meter in the vertical direction (indicated by arrows V in FIG. 4) and 2 tons per square meter in the horizontal direction (indicated by arrows H in FIG. 4). The sandwich panels may have other strength characteristics as will be appreciated in the art.
Internal stiffeners may be integrated into the panel core 43 to increase the overall stiffness of the sandwich panel 12. In one embodiment, the stiffeners are made from materials having the same thermal expansion properties as the materials used to construct the panel, such that the stiffeners expand and contract with the rest of the panel when the panel is heated or cooled.
The stiffeners may be made from the same material used to construct the outer layers of the panel. The stiffeners may be made from composite materials and may be placed perpendicular to the top and bottom of the panels and spaced, for example, at distances of 15 cm (centimeters), 25 cm, 50 cm, or 100 cm. Alternatively, the stiffeners may be placed at different angles, such as a 45-degree angle with respect to the top and bottom of the panel, or at another angle, as may be desired.
Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings.

Claims

1. A joint connecting a sandwich panel to a foundation comprising,

a sandwich panel comprising a core and two outer layers separated from one another by the core;

an anchor in the foundation;

a U-shape member having two side walls and a bottom wall extending between the sidewalls, the bottom wall defining a opening that is aligned with the anchor in the foundation; and

a securing member insertable through the opening in the bottom wall of the U-shape member and engaged to the anchor to secure the U-shape member to the anchor, wherein the U-shape member is connected to the outer layers of the sandwich panel by bonding material between the outer layers of the sandwich panel and the side walls of the U-shape member.

2. The joint of claim 1, further comprising bonding material between bottom wall of U-shape member and the foundation.

3. The joint of claim 2, wherein the securing member includes a bolt and a washer, wherein the washer is disposed between a head of the bolt and the bottom wall of the U-shape member.

4. The joint of claim 1, wherein the securing member includes at least one of a bolt, screw, washer or nut.

5. The joint of claim 1, further comprising at least one additional securing member and anchor, wherein the additional securing member is insertable through a second opening in the bottom wall of the U-shape member and secured to a second anchor in the foundation.

6. A method of joining a sandwich panel to a foundation with a U-shape member, wherein the U-shape member comprises a bottom wall and two side walls connected to one another by the bottom wall, the bottom wall having a opening defined by the bottom wall, the method comprising:

setting an anchor into a foundation;

connecting the U-shape member to the foundation with bonding material;

inserting a securing member through the opening in the bottom wall of the U-shape member and engaging the securing member to the anchor to secure the U-shape member to the foundation;

inserting an edge portion of a sandwich panel into the U-shape member; and

connecting the sandwich panel to the U-shape member with bonding material.

7. The method of claim 6, wherein the method further comprises placing a washer between a head of the securing member and the bottom wall of the U-shape member.

8. The method of claim 6, further comprising inserting a second securing member through a second opening in the bottom wall of the U-shape member and engaging the additional securing member to an additional anchor.

9. The method of claim 6, wherein the step of connecting the U-shape member to the foundation includes applying bonding material between the outer layers of the sandwich panel and the side walls of the U-shape member.

10. A joint connecting a sandwich panel to a foundation member, the joint comprising:

a wall comprised of at least one sandwich panel having a core and two outer layers separated from one another by the core;

a U-shape member extending along an edge of the wall, the U-shape member having a bottom wall and two side walls connected to one another by the bottom wall, wherein each of the side walls of the U-shape member are connected to respective outer layers of the wall, and wherein the bottom wall of the U-shape member includes a opening;

a foundation member;

at least one anchor set in the foundation member; and

at least one connection between the U-shape member and the foundation, wherein the connection is comprised of a bolt inserted through the opening in the bottom wall of the U-shape member and engaged to the anchor and bonding material between the bottom wall of the U-shape member and the foundation member.

11. The joint of claim 10, wherein the bottom wall of the U-shape member includes a second opening, and wherein the connection further comprises a second bolt inserted through the second opening and engaged to a second anchor in the foundation.

12. The joint of claim 10, wherein the U-shape member further comprises a number of openings in the bottom wall, and the connection between the U-shape member and the foundation further comprises, a number of bolts inserted through the openings in the bottom wall of the U-shape member and engaged to a number of anchors in the foundation.

13. A method of building construction, comprising

attaching a U-shape member to a building foundation,

placing an edge portion of a sandwich panel in the U-shape member, and

bonding the edge portion to the U-shape member.

14. The method of claim 13, said attaching comprising using a rigid member attached to the building foundation and securing the rigid member to the U-shape member.

15. The method of claim 13, said attaching comprising placing a bonding material between the building foundation and the generally U-shape member.

16. The method of claim 13, said bonding comprising applying a bonding material between side walls of the sandwich panel and side walls of the generally U-shape member.

17. The method of claim 13, further comprising using the sandwich panel as a wall of the building.

18. The method of claim 13, wherein the sandwich panel includes a relatively easily deformable portion sandwiched between respective relatively non-deformable outer layers, wherein said attaching comprises using a relatively rigid member having an end exposed to the relatively easily deformable portion of the sandwich panel, and pressing the sandwich panel against such rigid member end to cause such end portion of the sandwich panel to at least partially envelop such rigid member end.

19. The method of claim 18, further comprising applying bonding material between the end/edge of the sandwich panel and the bridge portion of the generally U-shape member.