FIELD QF THE INVENTION

The invention relates to a composite panel formed of a concrete slab and sheet metal studs, and to a stud for such a panel, and to dual spaced apart concrete slabs bonded integrally with such studs in spaced apart relation , and a method of manufacture.

BACKGROUND OF THE INVENTION

Construction panels known as "thin shell " panels have been known for some time. Such panels consist of a frame work of sheet metal reinforcing studs, and a slab of thin concrete , The studs have side edges which are partially embedded in the concrete. This provides an advantageous construction member. The concrete provides a light weight economical wall and the sheet metal studs provide reinforcement. In addition the sheet metal studs enable interior dry wail to be attached , without the need for additional wall framing on the interior. However heating losses caused by thermal transmission through the studs, prevent some thin shel! slab systems from achieving wide acceptance . In addition some of these simpler thin shell systems incorporated sheet metal studs which did not meet fire safety standards, and tended ^ψ o buckle when subjected to prolonged high temperatures.

An improved example of such a composite panel is shown in US Patent 4,909,007, Inventor E R Bodnar.

This composite panel employed studs of an unusual design , having spaced apart openings . This form of stud had reduced thermal transmission compared to plain solid web studs.

Studs of this type have a better fire rating than plain studs, which was another advantage.

Another form of construction member is shown in US Patent 6,708,459 Inventor E F

This form of construction member provided dual slabs of thin shell concrete. Both slabs were reinforced by sheet metal studs, extending between the two slabs.

This form of construction had greater strength , which was advantageous for forming , for example , floors or walls , of greater strength. In addition thermal insulation could be incorporated as a sandwich between the two slabs.

However this form of construction required the use of reiativeiy complex additional attachments to be connected to the sheet meta! studs. These attachments were in the form of embedment devices , screwed or fastened to the studs. The devices were required to provide for some form of embedment in the second concrete slab. This increased the cost of the thin shell pane! with two slabs and slowed down production. Clearly it is desirable to provide an improved form of stud, having improved thermal efficiency, an improved fire rating, and capable of being made from thinner

gauge metal.

Such a stud should be capable to being made with a single embedment edge for use with a single concrete slab, leaving a side flange on the other edge of the stud, for attachment of interior wall finishes, eg. Dry wall.

Thermal insulation may be placed between the studs in exterior walls. Et is also desirable to make such an improved stud with two embedment edges , for use with dual concrete slabs.

Preferably there will be provided an advanced method of making such a dual slab composite panel

BRIEF SUMMARY OF THE INVENTION

With a view to providing an improved thin she!! composite panel member , having at least one thin concrete slab and a plurality of sheet metal studs partly embedded in the slab, and providing reinforcing for the slab, and being characterised by a thin shell composite panel member having a concrete slab , and sheet metal reinforcing studs, partly embedded in said slab at spaced apart locations , and wherein each said sheet rnetai reinforcing stud comprises, a sheet metal web, a plurality of main web openings formed at spaced intervals and defining ribs between said main web openings, rib openings at the ends of each rib , rib flanges around the rib openings, web flanges ^? oπτιed around each said main web opening substantially normal to the plane of said web, reinforcing channels formed by additional bends in some said web flanges , extending along opposite sides of said web main openings, side flanges formed along each side of said web , an embedment strip formed along one said side flange , concrete flow openings in said embedment strip at spaced intervals, and a lock strip formed on said embedment strip.

Preferably the stud will have embedment strips along both said sides of said web, and poncrete ffow openings therein, and lock strips along both such embedment strips. Preferably the main web openings are formed with four radiussed corners, and with four linear sides extending between the corners.

preferably two of the linear sides will be spaced apart and parallel to each other and parallel to the side edges of the web, and including inner flanges formed on said linear sides, and bends in said inner flanges forming the same into generally three-sided reinforcing channels.

Preferably the other two linear sides will be provided with generally triangular flange

Preferably the web is formed with lengthwise indentations, running between the web mπain openings and the web side flanges .

Preferably the side flanges are also provided with lengthwise indentations .

In a further embodiment the web is formed with said side flanges extending out to a first side of said web and with concrete flow openings in said web adjacent to said side flanges , and said concrete flow openings being formed by punching out portions of sasd web so as to deflect locking tab portions extending outwardly to a second side of said web, in a plane generally co planar with said side flanges, for embedment in said concrete.

'The invention also provides a method of making a dual slab composite panel, by oouring a first pane!, and embedding a grid of studs having first and second

embedment edges , with their first embedment edges in the first panel, and then placing thermal insulation material between the studs, leaving the second embedment edges exposed above the insulation material, and then pouring a second slab onto the nsulation material, the material of the second slab flowing around the exposed second embedment edges of the studs and embedding them in the second slab, and allowing the two slabs to cure

The various features of novelty which characterize the invention are pointed out with more particularity in the claims annexed to and forming a part of this disclosure. For a ₍ better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.

IN THE DRAWINGS

Figure 1 is a schematic perspective of a composite construction panel, showing a single concrete slab, and a plurality of steel reinforcing studs;

Figure 2 is a perspective of a stud for reinforcing a single slab;

Figure 3 is a cut away side elevation of slab and single stud , of Fig 2;

Figure 4 is a side elevation of a stud for reinforcing a dual slab composite panel; Figure 5 is a section along line 5-5 of Fig 4;

Figure 6 is a perspective of a dual slab composite panel;

'Fjguire 7 is a section along line 7-7 of Fig 6;

Figure 8 is a perspective of a further embodiment of stud for a dual slab composite 'panel; and,

Figure 9 is a section along line 9 - 9 of Fig 8.

DESCRIPTION OF A SPECIFIC EMBODIMENT

Referring to Fig 1 it will be appreciated that this is a schematic illustration of a typical thin she!! composite panel (P ) to which the invention relates. St comprises a concrete slab (C ) and a plurality of sheet metal reinforcing studs (S ), arranged in parallel spaced apart relation. Portions of the sheet metal reinforcing studs (S ) are embedded in the concrete slab (C ) . Typically top (and bottom) members (M ) are attached to the top and bottom ends of the sheet metal reinforcing studs (S ) , so as to hold the sheet metal reinforcing studs (S ) in a predetermined parallel relation prior to embedment in the concrete slab (C ) . The top and bottom members (M ) will typicaϋy be simple sheet metal C-sections , with the ends of the sheet metal reinforcing studs (S ) being received within in the C-section shapes.

From this brief explanation, it will be understood that the invention relates to an improved thin she!! composite panel member using an improved sheet metal reinforcing stud having advanced features. The invention further relates to providing a thin shell composite panel member which has dual concrete slabs

(Fig 8 and 7, described below, and to a stud extending between the two slabs..

The sheet metal reinforcing studs (10 ) are shown in Fig 2 and 3.

Stud (10 ) has a sheet metal web (12 ) of planar sheet metal. Main web openings (14 ) are punched out of sheet metal web (12 ) at spaced intervals. Each main web opening (14 ) , in this embodiment is of generally four sided quadrilateral shape. It has two linear parallel sides (16 and 18), one being shorter and the other longer , and spaced apart and parallel with one another, and aligned with the longitudinal axis (20 ) of the sheet metal web (12 ) . The main web openings (14 ) have two non parallel linear sides (22 and 24 ) , extending diagonally from side to side of the

sheet metal web (12 ) .

The four sides are joined by radiussed corners (26 ) . Along the two parallel linear sides (16 and 18) there are formed web flanges (28 ) , integral with the metal of the sheet metal web (12 ) . The web flanges (28 ) are formed with a first bend (30 ) normal to the plane of the sheet metal web (18 ) , and with a second bend (32 ) bending that portion into a plane parallel to the plane of sheet metal web (18 ) . This two bends form toe web flanges (28 ) into axial reinforcing channels extending along the longitudinal axis (20) of the sheet metal web (12 ) .

The two non-parallel linear sides (22 and 24 ) of two adjacent main web openings (14 ) form ribs (36 ) extending diagonally from side to side on the sheet metal web (12 ) . Rib flanges (38 ) extend along each side edge of each of ribs (36 ) being bent substantially normal to the plane of sheet metal web (12 ) . Triangular flange

portions (40 ) are formed on rib flanges (38 ) intermediate their ends, for additional reinforcement, being highest at a mid point, and tapering down at each end.

ft will be appreciated that , while the general thinking would suggest that , in order to ^educe thermal transmission across sheet metal web (12 ) , it would be desirable to ^r emove as much metal as possible, it has been found, contrary to such thinking , that it is in fact advantageous to remove somewhat less metal than would normally be thought to be desirable . According to the invention it is found that this can be achieved without any sacrifice in low thermal conductivity, and results in a surprising increase in strength. The main openings (14 ) are formed through the sheet metal web (12 ) of the sheet metal reinforcing stud (10 ) , according to the invention, are specifically placed so as to reduce thermal transmission at various locations across the sheet metal web (12 ) . The sheet metal that is deliberately left in the sheet metal reinforcing stud (10 ) , such as the ribs (36 ) , the iinear parallel sides (22 ) and the non parallel linear sides (24 ) , and the channels formed by web flanges (28) all contribute to giving the sheet metal reinforcing stud (10 ) greater strength to accommodate the stresses in use, while contributing little or nothing to increasing thermal transmissions across the sheet metal reinforcing stud (14 )

In order to still further inhibit thermal transmission across the sheet metal

rehforcing stud (10 ) is formed with rib openings (42 ) punched through the sheet metal web (12 ) at each end of each of ribs (36 ) . These rib openings (42 ) are formed with annular flanges (44 ) around each rib opening (42 ) , for greater strength.

In the embodiment of Fig 2 there is a side flange (46 ) formed normal to the plane of sheet metal web (18 ) , and a lip (48 ) is formed on the free edge of side flange (46 ) for reinforcement.

Such a side flange may be used for attachment of interior wail finishing materia!, typically dray wall panels, or the like (not shown).

Lengthwise flange indentations (50 ) are formed in side flanges (46 ) to provide greater strength. Such indentations also assist in the fastening of wall finishing panels. The indentations serve the additional function of guiding dry wall screws (not shown), if such are used.

A partial flange (52 ) is formed along the other side edge of sheet metal web (12 ) .

Partia! flange (52 ) has an embedment wail (54 ) formed on its free edge. Embedment wall (54 ) is bent outwardly at a non-right angle. Along the embedment wall (54 ) at spaced apart intervals there are a plurality of concrete flow openings (56 ) punched out of the sheet metal at spaced intervals . A locking strip (58 ) is formed along the free ecge of embedment wall (54 ) .

The locking strip (58 ) is bent at an angle to the embedment wall (54 ) . in this way the entire locking strip (58 ) can be immersed in the concrete material of slab (60) , and the embedment waf! (54 ) can be at least partially embedded, with concrete flowing through the concrete flow openings (58 ) .

With studs spaced at for example 24 inch centres, the entire concrete slab (60 ) and studs , forming the composite panel , can be reinforced, and the composite panel can then be securely fastened in position, typically forming an exterior waϋ of a building.

Lengthwise web indentations (62 ) are formed along the sheet metal web (12 ), for still greater strength

The sheet metal reinforcing studs (10 ) also provide load bearing support for upper floors, at least up to a certain predetermined number of floors. The various flanges (30) ₍ foιτning reinforcing channels and the lengthwise indentations (50 ) and (62 ) all contribute to provide excellent load bearing properties.

The provision of main web opening (14 ) and rib openings (42 ) ensure that the sheet metal reinforcing studs (10 ) have a !ow thermal conductivity across their width, thus preventing the development of cold spots , known as ghosting , on the interior walls. In accordance with a further embodiment , shown in Figs 4 and 5, there may be provided a sheet metai reinforcing stud (70 ) having two partial flanges(72-74 ) , one along each side of the sheet metal reinforcing stud (70 ) , and having two embedment walls (76-78 ) , and two lock strips (80-82 ) ,on respective embedment walls (76-78). The sheet meta! reinforcing stud (70 ) has a similar sheet metal web (84 ) and main web openings (86 ) as the Fig 2 embodiment .

it further has reinforcing flanges forming channels (88 ) and ribs, and rib flanges , and rib openings (90 ) , as in the Fig 2 embodiment .

However this embodiment is designed for use with dual slabs of concrete, and for that reason both embedment walls (76-78 ) have flow openings (92-94 ) and lock strips (80-

82 ) .

This embodiment of sheet metal reinforcing stud (70 ) can then be used to fabricate a thin shell composite panel member (104 ) with two concrete slabs (106-108 ), as

.shown in Figs 6 and 7. The two concrete slabs (106-108 ) are spaced apart , being connected to the respective embedment strip (76-78 ) and lock strip (80-82 ) on opposite side edges of the same sheet metal reinforcing stud (70 ) .

The reinforcement and increased strength of this dual slab thin shell composite pane! member comes in part from the embedment of each of the embedment strip and lock strip in its respective concrete slab (106-108 ) . The concrete slabs (106-108 ) are effectively joined together, although separate, and are both reinforced by the same sheet metal reinforcing stud (70 ) .

This embodiment can be used for much heavier duty applications such as flooring , roofing , and for erecting walls where much greater strength is required than can be achieved in a thin shell composite panel member (10 ) with on!y a single

concrete slab (12 ) .

The manufacture of the thin she!! composite pane! member (104 ) with

dL aϊ concrete slabs (106-108 ) can be achieved in two ways.

The first method is simply to pour a first concrete slab (106 ) and then lower a grid of sheet metal reinforcing studs (70 ) down onto the concrete slab (106 ), so that the first lock strip (80 ) and embedment wall (76 ) become immersed in the concrete

slab (106 ) .

'After the concrete slab (106 ) has cured and set, then the entire assembly could then be lifted and rotated over. The second concrete slab (108 ) can then be poured, and the second lock strip (82 ) and embedment wall (78 ) can then be immersed in the second concrete slab (108 ) .

However this may take time, and involve complex handling .It is preferred that the dual slab thin shell composite panel member (104 ) be formed by simply pouring the first concrete slab (106 ) . Then the first embedment walls (76) of the sheet metal reinforcing studs (70 ) are immersed in the first slab (106).

Then thermal insulation blocks (110 ) are inserted between the sheet metal reinforcing studs (70 ), leaving the second embedment walls (78) exposed above the insulation blocks. Then the second concrete slab (108 ) can be poured directly over the thermal insulation blocks (110 ) , covering and immersing the second embedment walls (78 ) and second lock strips (82 ) .

τhe entire assembly can then be allowed to cure , with both slabs curing substantially at the same time

This second method reduces handling and repositioning of the product , and also provide the interior of the thin shell composite pane! member (104 ) with thermal msuiation incorporated directly into it as part of the manufacturing process.

A further embodiment of reinforcing stud (120 ) is shown in Figs 8 and 9.

In this embodiment the stud has a sheet metal web (122 ) , with main openings (124 ) and channels ( 126) afong opposed linear sides of the openings. Diagonal ribs (128 ) extend between openings (124 ) . Rib openings (130 ) are formed at each end on each rib (128 ) .

Lengthwise indentations (132 ) extend along web (122 ) . Ail of these features are simϋar to the same features in the Fig 4 and 5 embodiment .

Web (122 ) is somewhat wider than the web of the stud in Figs 4 and 5, for reasons explained below.

The embodiment differs from the Fig 4 and 5 embodiment in that there are two web flanges (134 ) and (136 ) formed along opposite side edges of the web (122 ) Web flanges (134-138 ) are bent normal to the plane of web (120 ) . Lengthwise

indentations (138 ) are formed along web flanges (134-136 ) .

Concrete flow openings (140 ) and (142 ) are formed through web (122 ) along the junction with web flanges (134-136 ) . The concrete flow openings are formed by punching out generally trapezoidal locking tabs (144 ) . Locking tabs (144 ) are bent out norma- to the plane of web (122 ) , and extend in a direction opposite to the direction of Web flanges (134-136 ), but lie in a common plane with web flanges (134-136 ) .

The embodiment of stud may be used in forming dual slab composite panels, similar to panels shown in Fig 6 and 7 .

The entire web flange and locking tabs along each edge of the stud may be immersed and embedded in respective slabs of concrete. The extra width of the web provides a sufficient depth of the web along each edge to accommodate the thickness of the concrete slab on each side.

However it will also be apparent that this stud can also be used, for reinforcing a single slab . The fact that the stud has web flanges and locking tabs , bent norma! to the plane of the web, and both lying in a common plane, would make it suitable for attachment of wall finishing panels, if desired.

The foregoing is a description of a preferred embodiment of the invention which is given here by way of example only. The invention is not to be taken as limited to any of the specific features as described, but comprehends all such variations thereof as come within the scope of the appended claims.