CA2407253C - Fast track building systems - Google Patents
Fast track building systems Download PDFInfo
- Publication number
- CA2407253C CA2407253C CA002407253A CA2407253A CA2407253C CA 2407253 C CA2407253 C CA 2407253C CA 002407253 A CA002407253 A CA 002407253A CA 2407253 A CA2407253 A CA 2407253A CA 2407253 C CA2407253 C CA 2407253C
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- flange
- wall
- base track
- floor
- joist
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Classifications
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B5/00—Floors; Floor construction with regard to insulation; Connections specially adapted therefor
- E04B5/16—Load-carrying floor structures wholly or partly cast or similarly formed in situ
- E04B5/32—Floor structures wholly cast in situ with or without form units or reinforcements
- E04B5/36—Floor structures wholly cast in situ with or without form units or reinforcements with form units as part of the floor
- E04B5/38—Floor structures wholly cast in situ with or without form units or reinforcements with form units as part of the floor with slab-shaped form units acting simultaneously as reinforcement; Form slabs with reinforcements extending laterally outside the element
- E04B5/40—Floor structures wholly cast in situ with or without form units or reinforcements with form units as part of the floor with slab-shaped form units acting simultaneously as reinforcement; Form slabs with reinforcements extending laterally outside the element with metal form-slabs
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/18—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons
- E04B1/24—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons the supporting parts consisting of metal
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B5/00—Floors; Floor construction with regard to insulation; Connections specially adapted therefor
- E04B5/02—Load-carrying floor structures formed substantially of prefabricated units
- E04B5/10—Load-carrying floor structures formed substantially of prefabricated units with metal beams or girders, e.g. with steel lattice girders
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
- E04C3/00—Structural elongated elements designed for load-supporting
- E04C3/02—Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; Braces
- E04C3/29—Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; Braces built-up from parts of different material, i.e. composite structures
- E04C3/293—Joists; Girders, trusses, or trusslike structures, e.g. prefabricated; Lintels; Transoms; Braces built-up from parts of different material, i.e. composite structures the materials being steel and concrete
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/18—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons
- E04B1/24—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons the supporting parts consisting of metal
- E04B1/2403—Connection details of the elongated load-supporting parts
- E04B2001/2448—Connections between open section profiles
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/18—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons
- E04B1/24—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons the supporting parts consisting of metal
- E04B2001/2484—Details of floor panels or slabs
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- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Chemical & Material Sciences (AREA)
- Composite Materials (AREA)
- Rod-Shaped Construction Members (AREA)
- Forms Removed On Construction Sites Or Auxiliary Members Thereof (AREA)
Abstract
This invention introduces two new types of light gauge steel load-bearing wall systems for supporting concrete topped floors on Open-Web-Steel-Joists (OWSJ) and deep- profile composite floor deck, respectively, and a composite steel beam system supporting concrete topped floors on OWSJ. Both load-bearing wall systems incorporate perforated light gauge steel studs on specialized bottom tracks complete with cutouts and discrete load-bearing blocks for OWSJ support. The new composite steel beam system incorporates, on the top flange of the beam, similar specialaized tracks modified with perforations for passage of shear heads from the steel beam. The specialized bottom tracks act as forming for a continuous reinforced concrete beam as part of the load-bearing wall system and/or composite beam-perimeter wall system. The invention allows upper-storey perimeter stud walls and load-bearing walls to proceed before concreting the floor, encases the bottom of the studs in concrete, and permits composite beam construction in OWSJ-on- steel-beams floor systems.
Description
Disclosure Brief Summary of the Invention For multi-storey buildings, this invention introduces two new types of light gauge steel load-bearing mall systems for suppoz-ting concrete topped floors on Open-Web-Steel-Joists (OWSJ) and deep-profile composite floor deck, respectively, and a composite steel beam system supporting concrete topped floors on OWSJ.
Both load-bearing wall systems incoparate laerfarated Light gauge steel studs on specialized bottom tracks complete with cutouts acid discrete load-bearing blacks for OWS,I suppou. ~1'he specialized bottom tracks act as forming for a continuous reinforced concrete beam as part of the load-bearing wall system.
'hhe new composite steel beam system incorporates, an the top Mange of the beam, a specialized perforated track complete with cutouts and discrete load-bearing blocks for OWSJ support, and evenly spaced holes in the track for the passage of shear connectors shop welded to the beam.
Light gauge steel studs in this invention have at least one hale at the bottom at specified locations, and may have perforations along the long of the studs.
In load-bearing-wall construction, the objectives of the invention are:
1. To allow the upper floor framing to proceed prior to the pouring of floor concrete;
Both load-bearing wall systems incoparate laerfarated Light gauge steel studs on specialized bottom tracks complete with cutouts acid discrete load-bearing blacks for OWS,I suppou. ~1'he specialized bottom tracks act as forming for a continuous reinforced concrete beam as part of the load-bearing wall system.
'hhe new composite steel beam system incorporates, an the top Mange of the beam, a specialized perforated track complete with cutouts and discrete load-bearing blocks for OWSJ support, and evenly spaced holes in the track for the passage of shear connectors shop welded to the beam.
Light gauge steel studs in this invention have at least one hale at the bottom at specified locations, and may have perforations along the long of the studs.
In load-bearing-wall construction, the objectives of the invention are:
1. To allow the upper floor framing to proceed prior to the pouring of floor concrete;
2. To provide a continuous reinforced concrete beam around the perimeter, and under load-bearing walls and demising walls for added strength and rigidity and increased inter-floor and inter-suite sound and fire separation;
3. To substantially increase load-bearing capacity and stiffness of the bearing wall by encasing the bottom of the studs in concrete, and 4. To provide anchorage against uplift at the floor elevation.
In post-and-beam construction, the objectives of the invention are:
1. To allow building enclosure to proceed prior to the pouring of floor concrete;
2. To provide a continuous reinforced concrete beam around the perimeter for added strength and rigidity and increased inter-floor and inter-suite sound and fire separation;
3. To substantially increase the performance of the wind-bearing metal stud wall by encasing the bottom of the studs in concrete, and 4. To make possible the use of composite steel beam construction for supportin~~ concrete-tapped floor on ()WSJ''s.
Cross-Reference to Related Applications U.S. Patent Documents 4,486,993 Dec., 1984 Graham et al.
In post-and-beam construction, the objectives of the invention are:
1. To allow building enclosure to proceed prior to the pouring of floor concrete;
2. To provide a continuous reinforced concrete beam around the perimeter for added strength and rigidity and increased inter-floor and inter-suite sound and fire separation;
3. To substantially increase the performance of the wind-bearing metal stud wall by encasing the bottom of the studs in concrete, and 4. To make possible the use of composite steel beam construction for supportin~~ concrete-tapped floor on ()WSJ''s.
Cross-Reference to Related Applications U.S. Patent Documents 4,486,993 Dec., 1984 Graham et al.
5,782,047 Jul., 1998 de Quesada 5,787,665 Aug., 1998 Carlin et al 5,822,940 Oct., 1998 Carlin et al 5,881,516 Mar., 1999 Luedtke.
5,983,577 Nov., 1999 Hays 6,050,045 Apr., 2000 Campbell 6,263,628 Jul., 2001 Griffin et al 6,276,094 Aug., 2001 Hays 6,293,057 Sep., 2001 Hays et all 6,298,617 Oct., 2001 de Quesada 6,318,044 Nov., 2001 Campbell 6,389,778 May 2002 Strange Background Information and Prior Art Load-BearingWall Construction In conventional construction of mufti-storey structures comprising load-bearing walls, platform framing technique is used. As the name suggests, platform framing relies on the floor assembly to provide a platform for subsequent framing construction. The lower floor supporting elements, usually the load-bearing walls, are constructed, then the floor elements installed, directly bearing on the supporting elements below. The follow-up bearing walls are then constructed, followed by the next upper floor assembly. The process repeats itself until the roof elements are installed. All modern floor systems involve the use of concrete as an integral part of the floor assembly. The fact that subsequent floor construction follows the completion of the floor assembly below means a significant delay in waiting for the concrete to cure.
Attempts have been made to eliminate/minimize the delay in platform construction. U.S. Pat.
No. 4,486,993 by Graham et al, No. 5,881,516 by l.,uedtke, and No. 5,782,047 as well as No.
6,298,617 by de Quesada, deal, in varying degrees, with methods of constructing bearing walls whereby the upper wall assembly can proceed before completion of the floor elements.
The first one, No. 4,486,993 by Graham et al, employs hot rolled angles attached to a foam-core latticed bearing wall for floor assembly support.
U.S. Pat. No. 5,782,047 by de Quesada employs hot rolled ledge angles attached to light gauge C-shaped channel steel stud bearing walls for bearing support of the concrete-topped floor assemblies. Floor concrete may terminate at the sides of the load-bearing walls, or may be carried continuously between the upper and lower wall assemblies. In the latter case (with concrete running between upper and lower assemblies), the upper wall assembly is supported on equally spaced screw jack assemblies allowing the upper wall assembly to proceed before the floor concrete.
1n LJ.S. Pat. No. 6,298,417, de Quesada refined his earlier invention and discarded the use of hot rolled ledge angles attached to light gauge C-shaped channel steel stud bearing walls for floor support, and screw-assemblies between upper and lower walls as spacers to allow continuity of the concrete in the floor. In place of the hot-rolled Ledge angles, a hat section is placed on top of the lower wall panel, with legs projecting horizontally out to support floor joists. In place of screw jack assemblies. discrete connectors are used. These comlectors are shop welded to the bottom of the upper wall panel, and site welded to the top of the bottom panel.
U.S. Pat. No. 5,881,516 by Luedtke deals with load bearing wall systems wherein the axial load does not pass through the floor assembly. Wall systems include both wood and conventional steel stud bearing walls. Floor assemblies include wood joists, light gauge steel C joists, and low-profile composite steel decks. The floor assemblies are supported, outside of the plane of the bearing wall, by various metal devices.
Underlying all of the above-referenced U.S. Patent Documents is the premise of carrying the floor load outside of the plane of the bearing wall. This very premise, however, creates eccentricity in the loading, and significantly reduces the load carrying capacity of the bearing wall. Both L:uedtke (Patent No. 5,881,51G) and de Quesada (U.S. Pat. No.
5,782,047 and 6,298,417) deals with shallow floor assemblies, i.e. low-profile filoor decks and C-joists. ~I'he more common steel floor systems with OWSJ and deep profile composite floor decks ~~re not discussed. With significantly increased spans associated with these more common systems, the eccentric bearing details become costly and complicated.
While continuity of the concrete in the floor assembly is maintained within the plane of the load-bearing walls to maintain continuous inter-floor fire and acoustic separation across the bearing walls , neither I~uedtke (Patent No. 5,881,516) nor Graham (L1.S. Pat.
No. 5,782,()47 and 6,298,417) makes stmetural use of the concrete. hence, secondary stmctural elements are still required over window or door openings in the wall panels.
These considerations lead to the development of the load-bearing wall systems described in this application. Detailed comparisons will be shown in the Section Comparison with Prior Art.
Post-and-Beam Construction In post-and-beam construction with OWS,T's, floor joists bear directly on the supporting beams, thus creating a space between the floor concrete and the supporting beams. This bearing detail is the only reason for precluding the use of composite beam construction in the steel joist-on-beam construction. This invention provides an intermediate bearing element to support the joists and allows for the floor concrete to be in contact with the steel beam. This intermediate bearing device and related concrete enclosures make possible composite action between a deep T- or L-shaped concrete section and the steel beam, and constitute the embodiments of the invention as applied to post-and-beam construction.
Brief Description of the Several Views of the Drawing Figures 1 A, 1 B, and 1 C show the sectional view, the elevation view, and the isometric view, respectively, of exterior load-bearing wall panels for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 1 - at a floor joint on the perimeter of a mufti-storey structure. Figure 1D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 1 in conjunction with the "concrete-topped steel deck on OWSJ" floor system at an exterior load-bearing wall.
Figures 2A, 2B, and 2C show the sectional view, the elevation view, and the isometric view, respectively, of interior load-bearing wall panels for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 2 - at a floor joint on the perimeter of a mufti-storey structure. Figure 2D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 2 in conjunction with the "concrete-topped steel deck on OWSJ" floor system at an interior load-bearing wall.
Figures 3A, 3B, and 3C show the sectional view, the elevation view, and the isometric view, respectively, of exterior load-bearing wall panels for the support of concrete-topped deep profile composite deck floor assembly - hereinafter referred as embodiment 3 -at a floor joint on the perimeter of a mufti-storey structure. Figure 3D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 3 in conjunction with the "concrete-topped deep profile composite deck" floor system at an exterior load-bearing wall.
Figures 4A, 4B, and 4C show the sectional view, the elevation view, and the isometric view, respectively, of exterior composite beam for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 4 - at a floor joint on the perimeter of a mufti-storey structure. Figure 4D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 4 in conjunction with the "concrete-topped deep profile composite deck" floor system and perimeter wind-bearing stud wall.
Figures SA, SB, and SC show the sectional view, the elevation view, and the isometric view, respectively, of interior composite beam for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 5 - at a floor joint of a multi-storey structure. Figure SD shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 5 in conjunction with the "concrete-topped deep profile composite deck" floor system.
List of Reference Numerals Utilized in the Drawing 1. Exterior closure track for LBW-OWSJ system 2. Top track with 100 mm long legs 3. Load bearing block 4. Perforated Steel stud (or stud with hole at bottom) 5. Open web steel joist 6. Metal deck ?. Concrete topping 8. Interior closure track for LBW-OWSJ system 9. Exterior closure track for LBW-Deep Profile Composite Deck system 10. Z-plate temporary ledger for LBW-Deep Profile Composite Deck system 11. Deep profile composite floor deck 12. Reinforcing bar in deep profile composite floor deck 13. Steel beam 14. Exterior closure track for Composite Beam-OWSJ system 15. Shear connectors 16. Interior closure track for Composite Beam-OWSJ system Detailed Description of the Invention While the subsequent descriptions of this invention are necessarily given in connection with specific apparatus and embodiments, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of the invention.
Specifically, concrete stops and closures, other than those described below and in the Drawing, can be easily developed for other types of joist floor systems.
Load-Bearing Wall (LBW) Systems Embodiment 1 - Exterior LBW for OWSJ
The first level of a load-bearing wall structure is the conventional load-bearing wall, with light gauge steel studs placed between top and bottom tracks.
Each wall panel above the lowest level, illustrated in Figs. 1 A, 1 B, and 1 C, comprises:
~ Light gauge steel track, 100 mm deep x width of the wall studs (2);
~ Light gauge steel studs, with or without perforations along the length, but with at least one perforation in the web at specified location at the bottom (4);
~ Special bottom track, with cutouts on the inside at specified locations for OWSJ and the exterior leg extending 100 mm above top of OWSJ for concrete closure (1);
~ Load-bearing block (150 x 100 tube section shown) at cutout locations (3).
Figure 1 D illustrates how Embodiment 1 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ (5) is placed on the load-bearing block (3) through the cutout in the bottom track (1). Steel deck (6) is installed on the OWSJ, but stopped on the inside face of the exterior wall. Reinforcing bars) is(are) placed in the bottom track. Number and size of reinforcing bars are governed by specific project requirements:
OWSJ span, floor loading, window and/or door opening size, etc. Floor concrete (?) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track, forming a reinforced concrete beam inside the wall.
Embodiment 2 - Interior LBW for OWSJ
Embodiment 1 is modified for application in an interior load-bearing wall supporting OWSJ's from both sides. The modification is achieved by having cutouts in both vertical legs of the bottom track (8), and having both vertical legs the same height.
Figure 2D illustrates how Embodiment 2 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ (5) is placed on the load-bearing block (3) through the cutout in the bottom track (8). Steel deck (6) is installed on the OWSJ, but stopped on the both faces of the interior wall. Reinforcing bars) is(are) placed in the bottom track. Number and size of reinforcing bars are governed by specific project requirements:
OWSJ span, floor loading, window and/or door opening size, etc. Floor concrete can be scheduled after the building is enclosed, and is allowed to flow into the bottom track, forming a reinforced concrete beam inside the wall.
Embodiment 3 - Exterior LBW for Deep-profiled Composite Deck The first level of a load-bearing wall structure is the conventional load-bearing wall, with light gauge steel studs placed between top and bottom tracks.
Each wall panel above the lowest level, illustrated in Figs. 3A, 3B, and 3C, comprises:
~ Light gauge steel track, 100 mm deep x width of the wall studs (2);
~ Light gauge steel studs, with or without perforations along the length, but with at least one perforation in the web at specified location at the bottom ( 1 );
~ Special bottom track, with cutouts on the inside at locations matching the flutes of the deep-profiled composite deck and the exterior leg above top of the deep-profiled composite deck for concrete closure (9);
~ Z-plate (10) for temporary support of deep profiled composite deck.
Figure 3D illustrates how Embodiment 3 is used for the support of concrete-topped deep-profiled composite deck floor system. The topped deep-profiled composite deck bears on the Z-plate(10) with flutes matching the cutout in the bottom track (9). The steel deck stops on the inside face of the exterior wall. Reinforcing bars) is(are) placed in the bottom track.
Number and size of reinforcing bars are governed by specific project requirements: OWSJ
span, floor loading, window and/or door opening size, etc. Reinforcing bars (12) in the steel deck are extended into the wall space and hooked to the longitudinal rebar(s) in the wall for anchorage. Floor concrete (7) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track, forming a reinforced concrete beam inside the wall.
Embodiment 4 - Exterior Composite Beam & Perimeter Wall for OWSJ
The composite steel beam comprises equally spaced shear connectors (15) shop welded to the top flange of a structural beam (13), normally a wide flange beam. The beam section, and shear connector design are governed by specific project requirements: beam span, OWSJ
span, and floor loading. Exterior wall panels, complete with opening framing for windows, are installed on top of the composite beam before concrete pour. Each wall panel comprises:
~ Light gauge steel track, 100 mm deep x width of the wall studs (2);
~ Light gauge steel studs, with or without perforations along the length, but with at least one perforation in the web at specified location at the bottom (4);
~ Special bottom track (14), with cutouts on the inside at specified locations for OWSJ, exterior leg extending 100 mm above top of OWSJ for concrete closure, and regularly spaced holes in the bottom for passage of shear connectors from the steel beam;
~ Load-bearing block (150 x 100 tube section shown) at cutout locations (3).
Figure 4D illustrates how Embodiment 4 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ (5) is placed on the load-bearing block (3) through the cutout in the bottom track (14). Steel deck (6) is installed on the OWSJ, but stopped on the inside face of the exterior wall. Floor concrete (7) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track. The shear heads (15) integrate the steel beam with a deep L-shaped concrete section, ensuring an efficient composite edge beam. The encasing of the wind-bearing studs in the concrete section provides for a stiff wall assembly, a feature especially useful under wide window openings.
Embodiment 5 - Interior Composite Beam for OWSJ
Embodiment 5 is modified for application in an interior composite beam supporting OWSJ's from both sides. The modification is achieved by having cutouts in both vertical legs of the bottom track (16), and having both vertical legs the same height.
Figure SD illustrates how Embodiment 5 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ is placed on the load-bearing block (3) through the cutout in the bottom track (16). Steel deck (6) is installed on the OWSJ, but stopped on the both faces of the bottom track. Floor concrete (7) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track. The shear heads (15) integrate the steel beam with a deep T-shaped concrete section, ensuring an efficient composite beam.
Fabrication / Construction Procedures We describe below one way the invention may be used in the construction of a multi-storey structure.
LBW- OWSJSystem Figures 1D and 2D detail the typical exterior/interior floor/wall joints, respectively, comprising the invention and the steel deck on open-web-steel joist floor system.
The wall construction is done, either on site or in a shop, in the following sequence:
(a) The first lifts of the wall panels complete with exterior sheathing are assembled.
Optionally, 100 mm deep tracks (2) may be used as the top and bottom tracks.
(b) Closure Tracks (1 and 9 for exterior and interior walls, respectively) are connected to the top tracks (2) of the bearing wall panels.
(c) Load-bearing blocks (3) are installed at the cutout locations, ready to receive floor joists.
(d) Cross-bracings (as per project design) and exterior sheathing are installed.
The upper wall panels are assembled similarly, except for the following modifications:
(a) The wall panels are assembled without the bottom track;
(b) The exterior sheathing are installed to an extent from the top of the Exterior Closure Track ( 1 ) of the lower wall panel to the top of the Exterior Closure Track ( 1 ) at the top.
The complete site construction may proceed as follows:
(a) The first lifts of the wall panels, complete with the closure tracks, are installed on top of the foundation.
(b) Temporary bracings for the wall panels are installed.
(c) Open web steel joists (5) are installed.
(d) Steel deck (6) is installed.
(e) Second lifts of wall panels are slid into the Closure Tracks (1).
(fj Rebars are threaded through the perforations in the steel studs (4).
The steps (b), (c), (d), (e) and (f) are repeated until the roof deck is installed. Concrete topping may be scheduled after the entire building enclosed as one continuous pour.
Alternatively, concrete for each floor may be scheduled immediately after the floor deck above is installed.
LBW -Deep Profile Deck System The construction procedures for load-bearing walls supporting deep-profile steel-deck floor assembly are similar to those for the open-web-steel joist floor system, with the following modifications:
1. No load-bearing track is required.
2. Z-Ledger (10) is connected to the bottom track for temporary support of the deep profile composite deck ( 11 ).
3. Deep Deck Closure Track (9) is used, in lieu of LBW-OWSJ closure track (1) .
Composite Beam-OWSJSystem Site construction procedure can be summarized as follows:
1. Structural steel trade erects the post-and-beam skeletal framing and bracing.
2. A single trade follows with the installation of (a) Enclosure Tracks (14, 16 for exterior and interior beams, respectively) and load bearing blocks (3);
(b) Open web steel joists (5) and steel decks (6) power-actuated connection systems;
(c) Perimeter walls 3. Repeat Step 2 for each floor.
4. General Contractor can schedule concrete pours as one continuous process after the entire building is enclosed. Alternately, concrete pour for the floor can be scheduled after installation of the perimeter walls for the floor and the steel deck for the floor above.
Comparison with Prior Art Load Bearing Wall Systems Since both Luedtke and de Quesada have patents for load-bearing wall systems which allow upper floor walls to proceed before pouring floor concrete, it is imperative to distinct the load-bearing wall systems in this invention (Embodiments 1 to 3) from their systems protected under their respective US patents. The following section will examine only the parts of their claims relevant to the present application - light gauge steel stud load-bearing walls and the floor assemblies they support.
Specifically, Luedtke in US Patent 5,881,516, "discloses building comprising a plurality of wall members comprising a plurality of metal wall members having track elements secured thereto, a plurality of bearing members having bearing surfaces projecting therefrom, and means connecting the bearing members to the track members. A multi-layer floor extends between the walls, the floor comprising a first layer having a first surface resting on the bearing surfaces such that wall axial loads do not pass through the floor construction."
The key to Luedtke invention is that metal devices projecting outside the plane of the load-bearing wall support the floor assemblies. This very premise, however, creates eccentricity in the loading, and significantly reduces the load carrying capacity of the bearing wall. In contrast, the load-bearing wall systems in this application support floor assemblies through a continuous reinforced concrete beam inside the wall assembly, with little or no eccentricity.
Though not at all clear from this Claims statement, a careful examination of US Patent 5,881,516 will show that the patent covers load-bearing walls supporting shallow floor assemblies only, i.e. shallow to medium depth (up to 75 mm) metal deck without joist support, and metal decks on C-shaped channel joists. Refer to Figs. 1, 2, 3, 4a, 4b, and 6 in US Patent 5,881,516. Compared to modern floor assemblies using OWSJ and deep profiled composite decks (200 mm deep or more), these shallow floor assemblies support relatively short spans (up to 4 meters for 75 mm decks and maybe 5 meters for C-shaped channel joists). When deep floor assemblies incorporating deep profiled composite decks and/or OWSJ are used, the concept of eccentric loading to a light gauge steel stud wall will prove almost impossible.
Another distinction between this application and Luedtke's invention lies in the use of concrete inside the load-bearing wall space. Luedtke uses conventional C-studs with solid webs. Concrete is compartmentalized in between studs, and there is no possibility of putting longitudinal reinforcing bars running the length of the load-bearing wall.
Consequently, concrete in the Luedtke system serves only to improve sound and floor ratings.
Structurally, it adds dead load to the wall, and consequently, increases loading to the lintels over window and door openings in the wall below. In contrast, the studs in this application will have to perforations at the bottom (and, optionally, along the length of the stud), allowing reinforcing bars to go through. Hence, a reinforced concrete beam can be properly designed to carry the floor load over any window or door openings, in addition to providing the improved sound and fire rating of the wall assembly. This reinforced beam eliminates the need for secondary lintels. which would still be required in Luedtke's system.
"de Quesada discloses a prefabricated system using wall panels having a combination of cold rolled light gauge sheet metal and hot rolled tubular steel. Panels are stacked one on top of each other to form vertical wall assemblies and may be welded directly with their top and bottom members or include intermediate shear connectors. Shear resistance or resistance to lateral forces is provided by a single continuous metal sheet either flat or corrugated (a deck type sheet) fastened to the steel studs or alternatively diagonal or V-shaped bracing.
Connectors between the wall panels provide a gap for a continuous concrete floor."
Careful examination of US Patents 6,298,617 and 5,782,047 shows that metal devices projecting outside the plane of the load-bearing wall support the floor assemblies, and only 'metal deck on C-shaped channel joists' floor assemblies are supported. Refer to Fig. 13 and Fig. 32 in Patent 6,298,617 and Figs. 8, 9, 11 in Patent 5,782,047.
While continuity of the concrete in the floor assembly is maintained within the plane of the load-bearing walls to maintain continuous inter-floor fire and acoustic separation across the bearing walls, there is not enough depth of concrete for any structural use.
(Refer to Fig. 13 and Fig. 32 in Patent 6,298,617 and Figs. 8, 9, 11 in Patent 5,782,047.) All the arguments that differentiate this application from Luedtke's invention apply, without modification, to de Quesada's inventions as well.
To sum up, both Luedtke and de Quesada incorporate metal devices projecting beyond the plane of load-bearing walls to carry the floor assemblies, with resulting eccentricity in loading for the load-bearing walls. Both deal with shallow floor assemblies.
Luedtke deals with metal deck up to 75 mm without joist support and 'metal deck on C-shaped channel joists' floor assemblies, while de Quesada only incorporates 'metal deck on C-shaped channel joists' floor assemblies. This application uses a continuous reinforced concrete beam inside the wall assembly to carry the floor loads, with little to zero eccentricity in loading.
Whereas both Luedtke and de Quesada limit their floor assemblies to shallow floor assemblies, this application specifically deals with deep floor assemblies with concrete topped steel deck on OWSJ and concrete on deep profile (200 mm or more) composite floor decks.
Composite Beam Systems There is no patented prior art for composite steel beams supporting concrete topped deck on OWSJ.
5,983,577 Nov., 1999 Hays 6,050,045 Apr., 2000 Campbell 6,263,628 Jul., 2001 Griffin et al 6,276,094 Aug., 2001 Hays 6,293,057 Sep., 2001 Hays et all 6,298,617 Oct., 2001 de Quesada 6,318,044 Nov., 2001 Campbell 6,389,778 May 2002 Strange Background Information and Prior Art Load-BearingWall Construction In conventional construction of mufti-storey structures comprising load-bearing walls, platform framing technique is used. As the name suggests, platform framing relies on the floor assembly to provide a platform for subsequent framing construction. The lower floor supporting elements, usually the load-bearing walls, are constructed, then the floor elements installed, directly bearing on the supporting elements below. The follow-up bearing walls are then constructed, followed by the next upper floor assembly. The process repeats itself until the roof elements are installed. All modern floor systems involve the use of concrete as an integral part of the floor assembly. The fact that subsequent floor construction follows the completion of the floor assembly below means a significant delay in waiting for the concrete to cure.
Attempts have been made to eliminate/minimize the delay in platform construction. U.S. Pat.
No. 4,486,993 by Graham et al, No. 5,881,516 by l.,uedtke, and No. 5,782,047 as well as No.
6,298,617 by de Quesada, deal, in varying degrees, with methods of constructing bearing walls whereby the upper wall assembly can proceed before completion of the floor elements.
The first one, No. 4,486,993 by Graham et al, employs hot rolled angles attached to a foam-core latticed bearing wall for floor assembly support.
U.S. Pat. No. 5,782,047 by de Quesada employs hot rolled ledge angles attached to light gauge C-shaped channel steel stud bearing walls for bearing support of the concrete-topped floor assemblies. Floor concrete may terminate at the sides of the load-bearing walls, or may be carried continuously between the upper and lower wall assemblies. In the latter case (with concrete running between upper and lower assemblies), the upper wall assembly is supported on equally spaced screw jack assemblies allowing the upper wall assembly to proceed before the floor concrete.
1n LJ.S. Pat. No. 6,298,417, de Quesada refined his earlier invention and discarded the use of hot rolled ledge angles attached to light gauge C-shaped channel steel stud bearing walls for floor support, and screw-assemblies between upper and lower walls as spacers to allow continuity of the concrete in the floor. In place of the hot-rolled Ledge angles, a hat section is placed on top of the lower wall panel, with legs projecting horizontally out to support floor joists. In place of screw jack assemblies. discrete connectors are used. These comlectors are shop welded to the bottom of the upper wall panel, and site welded to the top of the bottom panel.
U.S. Pat. No. 5,881,516 by Luedtke deals with load bearing wall systems wherein the axial load does not pass through the floor assembly. Wall systems include both wood and conventional steel stud bearing walls. Floor assemblies include wood joists, light gauge steel C joists, and low-profile composite steel decks. The floor assemblies are supported, outside of the plane of the bearing wall, by various metal devices.
Underlying all of the above-referenced U.S. Patent Documents is the premise of carrying the floor load outside of the plane of the bearing wall. This very premise, however, creates eccentricity in the loading, and significantly reduces the load carrying capacity of the bearing wall. Both L:uedtke (Patent No. 5,881,51G) and de Quesada (U.S. Pat. No.
5,782,047 and 6,298,417) deals with shallow floor assemblies, i.e. low-profile filoor decks and C-joists. ~I'he more common steel floor systems with OWSJ and deep profile composite floor decks ~~re not discussed. With significantly increased spans associated with these more common systems, the eccentric bearing details become costly and complicated.
While continuity of the concrete in the floor assembly is maintained within the plane of the load-bearing walls to maintain continuous inter-floor fire and acoustic separation across the bearing walls , neither I~uedtke (Patent No. 5,881,516) nor Graham (L1.S. Pat.
No. 5,782,()47 and 6,298,417) makes stmetural use of the concrete. hence, secondary stmctural elements are still required over window or door openings in the wall panels.
These considerations lead to the development of the load-bearing wall systems described in this application. Detailed comparisons will be shown in the Section Comparison with Prior Art.
Post-and-Beam Construction In post-and-beam construction with OWS,T's, floor joists bear directly on the supporting beams, thus creating a space between the floor concrete and the supporting beams. This bearing detail is the only reason for precluding the use of composite beam construction in the steel joist-on-beam construction. This invention provides an intermediate bearing element to support the joists and allows for the floor concrete to be in contact with the steel beam. This intermediate bearing device and related concrete enclosures make possible composite action between a deep T- or L-shaped concrete section and the steel beam, and constitute the embodiments of the invention as applied to post-and-beam construction.
Brief Description of the Several Views of the Drawing Figures 1 A, 1 B, and 1 C show the sectional view, the elevation view, and the isometric view, respectively, of exterior load-bearing wall panels for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 1 - at a floor joint on the perimeter of a mufti-storey structure. Figure 1D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 1 in conjunction with the "concrete-topped steel deck on OWSJ" floor system at an exterior load-bearing wall.
Figures 2A, 2B, and 2C show the sectional view, the elevation view, and the isometric view, respectively, of interior load-bearing wall panels for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 2 - at a floor joint on the perimeter of a mufti-storey structure. Figure 2D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 2 in conjunction with the "concrete-topped steel deck on OWSJ" floor system at an interior load-bearing wall.
Figures 3A, 3B, and 3C show the sectional view, the elevation view, and the isometric view, respectively, of exterior load-bearing wall panels for the support of concrete-topped deep profile composite deck floor assembly - hereinafter referred as embodiment 3 -at a floor joint on the perimeter of a mufti-storey structure. Figure 3D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 3 in conjunction with the "concrete-topped deep profile composite deck" floor system at an exterior load-bearing wall.
Figures 4A, 4B, and 4C show the sectional view, the elevation view, and the isometric view, respectively, of exterior composite beam for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 4 - at a floor joint on the perimeter of a mufti-storey structure. Figure 4D shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 4 in conjunction with the "concrete-topped deep profile composite deck" floor system and perimeter wind-bearing stud wall.
Figures SA, SB, and SC show the sectional view, the elevation view, and the isometric view, respectively, of interior composite beam for the support of concrete-topped steel deck on OWSJ floor assembly - hereinafter referred as embodiment 5 - at a floor joint of a multi-storey structure. Figure SD shows an isometric view of a typical intermediate floor/wall joint detail comprising embodiment 5 in conjunction with the "concrete-topped deep profile composite deck" floor system.
List of Reference Numerals Utilized in the Drawing 1. Exterior closure track for LBW-OWSJ system 2. Top track with 100 mm long legs 3. Load bearing block 4. Perforated Steel stud (or stud with hole at bottom) 5. Open web steel joist 6. Metal deck ?. Concrete topping 8. Interior closure track for LBW-OWSJ system 9. Exterior closure track for LBW-Deep Profile Composite Deck system 10. Z-plate temporary ledger for LBW-Deep Profile Composite Deck system 11. Deep profile composite floor deck 12. Reinforcing bar in deep profile composite floor deck 13. Steel beam 14. Exterior closure track for Composite Beam-OWSJ system 15. Shear connectors 16. Interior closure track for Composite Beam-OWSJ system Detailed Description of the Invention While the subsequent descriptions of this invention are necessarily given in connection with specific apparatus and embodiments, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of the invention.
Specifically, concrete stops and closures, other than those described below and in the Drawing, can be easily developed for other types of joist floor systems.
Load-Bearing Wall (LBW) Systems Embodiment 1 - Exterior LBW for OWSJ
The first level of a load-bearing wall structure is the conventional load-bearing wall, with light gauge steel studs placed between top and bottom tracks.
Each wall panel above the lowest level, illustrated in Figs. 1 A, 1 B, and 1 C, comprises:
~ Light gauge steel track, 100 mm deep x width of the wall studs (2);
~ Light gauge steel studs, with or without perforations along the length, but with at least one perforation in the web at specified location at the bottom (4);
~ Special bottom track, with cutouts on the inside at specified locations for OWSJ and the exterior leg extending 100 mm above top of OWSJ for concrete closure (1);
~ Load-bearing block (150 x 100 tube section shown) at cutout locations (3).
Figure 1 D illustrates how Embodiment 1 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ (5) is placed on the load-bearing block (3) through the cutout in the bottom track (1). Steel deck (6) is installed on the OWSJ, but stopped on the inside face of the exterior wall. Reinforcing bars) is(are) placed in the bottom track. Number and size of reinforcing bars are governed by specific project requirements:
OWSJ span, floor loading, window and/or door opening size, etc. Floor concrete (?) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track, forming a reinforced concrete beam inside the wall.
Embodiment 2 - Interior LBW for OWSJ
Embodiment 1 is modified for application in an interior load-bearing wall supporting OWSJ's from both sides. The modification is achieved by having cutouts in both vertical legs of the bottom track (8), and having both vertical legs the same height.
Figure 2D illustrates how Embodiment 2 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ (5) is placed on the load-bearing block (3) through the cutout in the bottom track (8). Steel deck (6) is installed on the OWSJ, but stopped on the both faces of the interior wall. Reinforcing bars) is(are) placed in the bottom track. Number and size of reinforcing bars are governed by specific project requirements:
OWSJ span, floor loading, window and/or door opening size, etc. Floor concrete can be scheduled after the building is enclosed, and is allowed to flow into the bottom track, forming a reinforced concrete beam inside the wall.
Embodiment 3 - Exterior LBW for Deep-profiled Composite Deck The first level of a load-bearing wall structure is the conventional load-bearing wall, with light gauge steel studs placed between top and bottom tracks.
Each wall panel above the lowest level, illustrated in Figs. 3A, 3B, and 3C, comprises:
~ Light gauge steel track, 100 mm deep x width of the wall studs (2);
~ Light gauge steel studs, with or without perforations along the length, but with at least one perforation in the web at specified location at the bottom ( 1 );
~ Special bottom track, with cutouts on the inside at locations matching the flutes of the deep-profiled composite deck and the exterior leg above top of the deep-profiled composite deck for concrete closure (9);
~ Z-plate (10) for temporary support of deep profiled composite deck.
Figure 3D illustrates how Embodiment 3 is used for the support of concrete-topped deep-profiled composite deck floor system. The topped deep-profiled composite deck bears on the Z-plate(10) with flutes matching the cutout in the bottom track (9). The steel deck stops on the inside face of the exterior wall. Reinforcing bars) is(are) placed in the bottom track.
Number and size of reinforcing bars are governed by specific project requirements: OWSJ
span, floor loading, window and/or door opening size, etc. Reinforcing bars (12) in the steel deck are extended into the wall space and hooked to the longitudinal rebar(s) in the wall for anchorage. Floor concrete (7) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track, forming a reinforced concrete beam inside the wall.
Embodiment 4 - Exterior Composite Beam & Perimeter Wall for OWSJ
The composite steel beam comprises equally spaced shear connectors (15) shop welded to the top flange of a structural beam (13), normally a wide flange beam. The beam section, and shear connector design are governed by specific project requirements: beam span, OWSJ
span, and floor loading. Exterior wall panels, complete with opening framing for windows, are installed on top of the composite beam before concrete pour. Each wall panel comprises:
~ Light gauge steel track, 100 mm deep x width of the wall studs (2);
~ Light gauge steel studs, with or without perforations along the length, but with at least one perforation in the web at specified location at the bottom (4);
~ Special bottom track (14), with cutouts on the inside at specified locations for OWSJ, exterior leg extending 100 mm above top of OWSJ for concrete closure, and regularly spaced holes in the bottom for passage of shear connectors from the steel beam;
~ Load-bearing block (150 x 100 tube section shown) at cutout locations (3).
Figure 4D illustrates how Embodiment 4 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ (5) is placed on the load-bearing block (3) through the cutout in the bottom track (14). Steel deck (6) is installed on the OWSJ, but stopped on the inside face of the exterior wall. Floor concrete (7) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track. The shear heads (15) integrate the steel beam with a deep L-shaped concrete section, ensuring an efficient composite edge beam. The encasing of the wind-bearing studs in the concrete section provides for a stiff wall assembly, a feature especially useful under wide window openings.
Embodiment 5 - Interior Composite Beam for OWSJ
Embodiment 5 is modified for application in an interior composite beam supporting OWSJ's from both sides. The modification is achieved by having cutouts in both vertical legs of the bottom track (16), and having both vertical legs the same height.
Figure SD illustrates how Embodiment 5 is used for the support of "concrete-topped steel deck on OWSJ" floor system. OWSJ is placed on the load-bearing block (3) through the cutout in the bottom track (16). Steel deck (6) is installed on the OWSJ, but stopped on the both faces of the bottom track. Floor concrete (7) can be scheduled after the building is enclosed, and is allowed to flow into the bottom track. The shear heads (15) integrate the steel beam with a deep T-shaped concrete section, ensuring an efficient composite beam.
Fabrication / Construction Procedures We describe below one way the invention may be used in the construction of a multi-storey structure.
LBW- OWSJSystem Figures 1D and 2D detail the typical exterior/interior floor/wall joints, respectively, comprising the invention and the steel deck on open-web-steel joist floor system.
The wall construction is done, either on site or in a shop, in the following sequence:
(a) The first lifts of the wall panels complete with exterior sheathing are assembled.
Optionally, 100 mm deep tracks (2) may be used as the top and bottom tracks.
(b) Closure Tracks (1 and 9 for exterior and interior walls, respectively) are connected to the top tracks (2) of the bearing wall panels.
(c) Load-bearing blocks (3) are installed at the cutout locations, ready to receive floor joists.
(d) Cross-bracings (as per project design) and exterior sheathing are installed.
The upper wall panels are assembled similarly, except for the following modifications:
(a) The wall panels are assembled without the bottom track;
(b) The exterior sheathing are installed to an extent from the top of the Exterior Closure Track ( 1 ) of the lower wall panel to the top of the Exterior Closure Track ( 1 ) at the top.
The complete site construction may proceed as follows:
(a) The first lifts of the wall panels, complete with the closure tracks, are installed on top of the foundation.
(b) Temporary bracings for the wall panels are installed.
(c) Open web steel joists (5) are installed.
(d) Steel deck (6) is installed.
(e) Second lifts of wall panels are slid into the Closure Tracks (1).
(fj Rebars are threaded through the perforations in the steel studs (4).
The steps (b), (c), (d), (e) and (f) are repeated until the roof deck is installed. Concrete topping may be scheduled after the entire building enclosed as one continuous pour.
Alternatively, concrete for each floor may be scheduled immediately after the floor deck above is installed.
LBW -Deep Profile Deck System The construction procedures for load-bearing walls supporting deep-profile steel-deck floor assembly are similar to those for the open-web-steel joist floor system, with the following modifications:
1. No load-bearing track is required.
2. Z-Ledger (10) is connected to the bottom track for temporary support of the deep profile composite deck ( 11 ).
3. Deep Deck Closure Track (9) is used, in lieu of LBW-OWSJ closure track (1) .
Composite Beam-OWSJSystem Site construction procedure can be summarized as follows:
1. Structural steel trade erects the post-and-beam skeletal framing and bracing.
2. A single trade follows with the installation of (a) Enclosure Tracks (14, 16 for exterior and interior beams, respectively) and load bearing blocks (3);
(b) Open web steel joists (5) and steel decks (6) power-actuated connection systems;
(c) Perimeter walls 3. Repeat Step 2 for each floor.
4. General Contractor can schedule concrete pours as one continuous process after the entire building is enclosed. Alternately, concrete pour for the floor can be scheduled after installation of the perimeter walls for the floor and the steel deck for the floor above.
Comparison with Prior Art Load Bearing Wall Systems Since both Luedtke and de Quesada have patents for load-bearing wall systems which allow upper floor walls to proceed before pouring floor concrete, it is imperative to distinct the load-bearing wall systems in this invention (Embodiments 1 to 3) from their systems protected under their respective US patents. The following section will examine only the parts of their claims relevant to the present application - light gauge steel stud load-bearing walls and the floor assemblies they support.
Specifically, Luedtke in US Patent 5,881,516, "discloses building comprising a plurality of wall members comprising a plurality of metal wall members having track elements secured thereto, a plurality of bearing members having bearing surfaces projecting therefrom, and means connecting the bearing members to the track members. A multi-layer floor extends between the walls, the floor comprising a first layer having a first surface resting on the bearing surfaces such that wall axial loads do not pass through the floor construction."
The key to Luedtke invention is that metal devices projecting outside the plane of the load-bearing wall support the floor assemblies. This very premise, however, creates eccentricity in the loading, and significantly reduces the load carrying capacity of the bearing wall. In contrast, the load-bearing wall systems in this application support floor assemblies through a continuous reinforced concrete beam inside the wall assembly, with little or no eccentricity.
Though not at all clear from this Claims statement, a careful examination of US Patent 5,881,516 will show that the patent covers load-bearing walls supporting shallow floor assemblies only, i.e. shallow to medium depth (up to 75 mm) metal deck without joist support, and metal decks on C-shaped channel joists. Refer to Figs. 1, 2, 3, 4a, 4b, and 6 in US Patent 5,881,516. Compared to modern floor assemblies using OWSJ and deep profiled composite decks (200 mm deep or more), these shallow floor assemblies support relatively short spans (up to 4 meters for 75 mm decks and maybe 5 meters for C-shaped channel joists). When deep floor assemblies incorporating deep profiled composite decks and/or OWSJ are used, the concept of eccentric loading to a light gauge steel stud wall will prove almost impossible.
Another distinction between this application and Luedtke's invention lies in the use of concrete inside the load-bearing wall space. Luedtke uses conventional C-studs with solid webs. Concrete is compartmentalized in between studs, and there is no possibility of putting longitudinal reinforcing bars running the length of the load-bearing wall.
Consequently, concrete in the Luedtke system serves only to improve sound and floor ratings.
Structurally, it adds dead load to the wall, and consequently, increases loading to the lintels over window and door openings in the wall below. In contrast, the studs in this application will have to perforations at the bottom (and, optionally, along the length of the stud), allowing reinforcing bars to go through. Hence, a reinforced concrete beam can be properly designed to carry the floor load over any window or door openings, in addition to providing the improved sound and fire rating of the wall assembly. This reinforced beam eliminates the need for secondary lintels. which would still be required in Luedtke's system.
"de Quesada discloses a prefabricated system using wall panels having a combination of cold rolled light gauge sheet metal and hot rolled tubular steel. Panels are stacked one on top of each other to form vertical wall assemblies and may be welded directly with their top and bottom members or include intermediate shear connectors. Shear resistance or resistance to lateral forces is provided by a single continuous metal sheet either flat or corrugated (a deck type sheet) fastened to the steel studs or alternatively diagonal or V-shaped bracing.
Connectors between the wall panels provide a gap for a continuous concrete floor."
Careful examination of US Patents 6,298,617 and 5,782,047 shows that metal devices projecting outside the plane of the load-bearing wall support the floor assemblies, and only 'metal deck on C-shaped channel joists' floor assemblies are supported. Refer to Fig. 13 and Fig. 32 in Patent 6,298,617 and Figs. 8, 9, 11 in Patent 5,782,047.
While continuity of the concrete in the floor assembly is maintained within the plane of the load-bearing walls to maintain continuous inter-floor fire and acoustic separation across the bearing walls, there is not enough depth of concrete for any structural use.
(Refer to Fig. 13 and Fig. 32 in Patent 6,298,617 and Figs. 8, 9, 11 in Patent 5,782,047.) All the arguments that differentiate this application from Luedtke's invention apply, without modification, to de Quesada's inventions as well.
To sum up, both Luedtke and de Quesada incorporate metal devices projecting beyond the plane of load-bearing walls to carry the floor assemblies, with resulting eccentricity in loading for the load-bearing walls. Both deal with shallow floor assemblies.
Luedtke deals with metal deck up to 75 mm without joist support and 'metal deck on C-shaped channel joists' floor assemblies, while de Quesada only incorporates 'metal deck on C-shaped channel joists' floor assemblies. This application uses a continuous reinforced concrete beam inside the wall assembly to carry the floor loads, with little to zero eccentricity in loading.
Whereas both Luedtke and de Quesada limit their floor assemblies to shallow floor assemblies, this application specifically deals with deep floor assemblies with concrete topped steel deck on OWSJ and concrete on deep profile (200 mm or more) composite floor decks.
Composite Beam Systems There is no patented prior art for composite steel beams supporting concrete topped deck on OWSJ.
Claims (53)
1. A wall assembly constructed upon a support surface, said assembly comprising:
(a) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
a.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and a.2 the first flange has a plurality of cutouts, each shaped to receive a structural joist;
said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward;
(b) a plurality of joist-support elements, each positioned upon the inner face of the base track's web member adjacent a corresponding joist cutout; and (c) a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges.
(a) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
a.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and a.2 the first flange has a plurality of cutouts, each shaped to receive a structural joist;
said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward;
(b) a plurality of joist-support elements, each positioned upon the inner face of the base track's web member adjacent a corresponding joist cutout; and (c) a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges.
2. The wall assembly of Claim 1 wherein at least one of the cutouts in the base track's first flange is configured to receive an open-web steel joist.
3. The wall assembly of Claim 1 wherein at least one of the cutouts in the base track's first flange is configured to receive a channel-shaped joist.
4. The wall assembly of Claim 1 wherein the upper edge of the base track's second flange coincides with a selected floor elevation.
5. The wall assembly of Claim 1 wherein the base track's second flange has a plurality of cutouts, each shaped to receive a structural joist.
6. The wall assembly of Claim 1 wherein at least one of the studs has a perforation for receiving a concrete reinforcement rod, said perforation being positioned below the upper edge of the base track's second flange.
7. The wall assembly of Claim 1 wherein at least one of the joist-support elements is a concrete block having a horizontal upper surface with an embedded steel plate.
8. The wall assembly of Claim 1 wherein at least one of the joist-support elements is a rectilinear steel tube section.
9. The wall assembly of Claim 1 wherein at least one of the joist-support elements is a light-gauge steel Channel section with downwardly-disposed flanges and a horizontally-disposed web member.
10. The wall assembly of Claim 1 wherein at least one of the joist-support elements is a light-gauge steel channel section with downwardly-disposed flanges and a horizontally-disposed web member, said web member having a steel reinforcing plate.
11. The wall assembly of Claim 1 wherein the support surface is the top track of a lower wall.
12. The wall assembly of Claim 1 wherein the support surface is the top flange of a structural steel beam.
13. The wall assembly of Claim 12, further comprising a plurality of shear connectors anchored to the top flange of the steel beam, said shear connectors being spaced apart and positioned between the studs of the wall panel.
14. A wall assembly constructed upon a support surface, said assembly comprising:
(a) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
a.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and a.2 the first flange has a continuous lip for supporting structural decking;
said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward; and (b) a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges.
(a) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
a.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and a.2 the first flange has a continuous lip for supporting structural decking;
said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward; and (b) a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges.
15. The wall assembly of Claim 14 wherein the base track's second flange has a continuous lip for supporting structural decking.
16. A wall assembly constructed upon a support surface, said assembly comprising:
(a) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
a.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and a.2 the first flange has a plurality of cutouts for receiving structural decking flutes;
said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward; and (b) a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges.
(a) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
a.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and a.2 the first flange has a plurality of cutouts for receiving structural decking flutes;
said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward; and (b) a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges.
17. The wall assembly of Claim 16 wherein the base track's second flange has a plurality of cutouts for receiving structural decking flutes.
18. The wall assembly of Claim 14 or Claim 16 wherein the support surface is the top track of a lower wall.
19. The wall assembly of Claim 14 or Claim 16 wherein the upper edge of the base track's second flange coincides with a selected floor elevation.
20. The wall assembly of Claim 14 or Claim 16 wherein at least one of the studs has a perforation for receiving a concrete reinforcement rod, said perforation being positioned below the upper edge of the base track's second flange.
21. The wall assembly of Claim 14 or Claim 16 wherein the support surface is the top flange of a structural steel beam.
22. The wall assembly of Claim 21, further comprising a plurality of shear connectors anchored to the top flange of the steel beam, said shear connectors being spaced apart and positioned between the studs of the wall panel.
23. A wall-and-floor subassembly comprising:
(a) a wall constructed upon a support surface and comprising:
a.1 an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member, and wherein the first flange has a plurality of cutouts, each shaped to receive a structural joist, said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward;
a.2 a plurality of joist-support elements, each positioned upon the inner face of the base track's web member adjacent a corresponding joist cutout; and a.3 a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges;
(b) a plurality of primary floor joists each having:
b.1 a first end disposed within one of the joist cutouts in the base track's first flange, and supported on a corresponding joist-support element; and b.2 a second end supported on a first auxiliary support structure, such that the top surfaces of the primary joists lie in a common horizontal plane.
(c) metal decking overlying and fastened to the primary joists; and (d) concrete topping placed over the metal decking and extending into the space between the first and second flanges of the base track, with the upper surface of the concrete topping being at a selected floor elevation.
(a) a wall constructed upon a support surface and comprising:
a.1 an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member, and wherein the first flange has a plurality of cutouts, each shaped to receive a structural joist, said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward;
a.2 a plurality of joist-support elements, each positioned upon the inner face of the base track's web member adjacent a corresponding joist cutout; and a.3 a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges;
(b) a plurality of primary floor joists each having:
b.1 a first end disposed within one of the joist cutouts in the base track's first flange, and supported on a corresponding joist-support element; and b.2 a second end supported on a first auxiliary support structure, such that the top surfaces of the primary joists lie in a common horizontal plane.
(c) metal decking overlying and fastened to the primary joists; and (d) concrete topping placed over the metal decking and extending into the space between the first and second flanges of the base track, with the upper surface of the concrete topping being at a selected floor elevation.
24. The wall-and-floor subassembly of Claim 23 wherein the upper edge of the base track's second flange coincides with a selected floor elevation.
25. The wall-and-floor subassembly of Claim 23 wherein:
(a) the base track's second flange has a plurality of joist cutouts;
(b) the subassembly further comprises a plurality of supplementary floor joists, each having a first end disposed within one of the joist cutouts in said second flange, and supported on a corresponding joist-support element, and having a second end supported on a second auxiliary support structure, such that the top surfaces of the supplementary joists lie in the same plane as the primary joists; and (c) the metal decking overlies and is fastened to both the primary and supplementary joists.
(a) the base track's second flange has a plurality of joist cutouts;
(b) the subassembly further comprises a plurality of supplementary floor joists, each having a first end disposed within one of the joist cutouts in said second flange, and supported on a corresponding joist-support element, and having a second end supported on a second auxiliary support structure, such that the top surfaces of the supplementary joists lie in the same plane as the primary joists; and (c) the metal decking overlies and is fastened to both the primary and supplementary joists.
26. The wall-and-floor subassembly of Claim 23, 24, or 25 wherein at least one of the studs has a perforation for receiving a concrete reinforcement rod, said perforation being positioned below the upper edge of the base track's second flange.
27. The wall-and-floor subassembly of Claim 23 wherein at least one of the joist-support elements is a concrete block having a horizontal upper surface with an embedded steel plate.
28. The wall-and-floor subassembly of Claim 23 wherein at least one of the joist-support elements is a rectilinear steel tube section.
29. The wall-and-floor subassembly of Claim 23 wherein at least one of the joist-support elements is a light-gauge steel Channel section with downwardly-disposed flanges and a horizontally-disposed web member.
30. The wall-and-floor subassembly of Claim 23 wherein at least one of the joist-support elements is a light-gauge steel channel section with downwardly-disposed flanges and a horizontally-disposed web member, said web member having a steel reinforcing plate.
31. The wall-and-floor subassembly of Claim 23 wherein the support surface is the top track of a lower wall.
32. The wall-and-floor subassembly of Claim 23 wherein the support surface is the top flange of a structural steel beam.
33. The wall-and-floor subassembly of Claim 32, further comprising a plurality of shear connectors anchored to the top flange of the steel beam, said shear connectors being spaced apart and positioned between the studs of the wall panel.
34. A wall-and-floor subassembly comprising:
(a) a wall constructed upon a support surface and comprising:
a.1 an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member, and wherein the first flange incorporates means for supporting fluted structural decking, said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward; and a.2 a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges;
(b) a plurality of elongate fluted structural decking units spanning between said decking support means and an auxiliary support means, with the upper surfaces of the decking units being at a common elevation; and (c) concrete topping placed over the metal decking and extending into the space between the first and second flanges of the base track, with the upper surface of the concrete topping being at a selected floor elevation.
(a) a wall constructed upon a support surface and comprising:
a.1 an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member, and wherein the first flange incorporates means for supporting fluted structural decking, said base track being positioned upon and anchored to the support surface, with its first and second flanges projecting vertically upward; and a.2 a wall panel comprising a plurality of spaced, light-gauge metal studs, the lower ends of said studs being disposed between the base track's first and second flanges;
(b) a plurality of elongate fluted structural decking units spanning between said decking support means and an auxiliary support means, with the upper surfaces of the decking units being at a common elevation; and (c) concrete topping placed over the metal decking and extending into the space between the first and second flanges of the base track, with the upper surface of the concrete topping being at a selected floor elevation.
35. The wall-and-floor subassembly of Claim 34 wherein the decking support means comprises a continuous lip associated with the base track's first flange.
36. The wall-and-floor subassembly of Claim 34 wherein the decking support means comprises a plurality of cutouts formed in the base track's first flange and shaped to receive the flutes of the structural decking.
37. The wall-and-floor subassembly of Claim 34 wherein the base track's second flange incorporates means for supporting fluted structural decking.
38. The wall-and-floor subassembly of Claim 34 wherein the support surface is the top track of a lower wall.
39. The wall-and-floor subassembly of Claim 34 wherein the upper edge of the base track's second flange coincides with a selected floor elevation.
40. The wall-and-floor subassembly of Claim 34 wherein at least one of the studs has a perforation for receiving a concrete reinforcement rod, said perforation being positioned below the upper edge of the base track's second flange.
41. The wall-and-floor subassembly of Claim 34 wherein the support surface is the top flange of a structural steel beam.
42. The wall-and-floor subassembly of Claim 41, further comprising a plurality of shear connectors anchored to the top flange of the steel beam, said shear connectors being spaced apart and positioned between the studs of the wall panel.
43. A structural subassembly comprising:
(a) a steel beam having a top flange and spanning between structural support elements;
(b) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
b.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and b.2 the first flange has a plurality of cutouts, each shaped to receive a structural joist;
said base track being positioned upon and anchored to the top flange of the steel beam, with its first and second flanges projecting vertically upward;
(c) a plurality of primary joists each having:
c.1 a first end disposed within one of the joist cutouts in the base track's first flange, so as to transfer vertical loading to the steel beam; and c.2 a second end supported on a first auxiliary support structure, such that the top surfaces of the primary joists lie in a common horizontal plane;
(d) a plurality of shear connectors anchored to the top flange of the steel beam, said shear connectors being spaced apart and positioned between the first ends of the primary joists;
(e) metal decking overlying and fastened to the primary joists; and (f) concrete topping placed over the metal decking and extending into the space between the first and second flanges of the base track, with the upper surface of the concrete topping being at a selected floor elevation.
(a) a steel beam having a top flange and spanning between structural support elements;
(b) an elongate light-gauge metal base track comprising a continuous web member having an inner face and an outer face, a continuous first flange, and a continuous second flange, wherein:
b.1 said first and second flanges are parallel and extend substantially perpendicularly from the inner face of the web member; and b.2 the first flange has a plurality of cutouts, each shaped to receive a structural joist;
said base track being positioned upon and anchored to the top flange of the steel beam, with its first and second flanges projecting vertically upward;
(c) a plurality of primary joists each having:
c.1 a first end disposed within one of the joist cutouts in the base track's first flange, so as to transfer vertical loading to the steel beam; and c.2 a second end supported on a first auxiliary support structure, such that the top surfaces of the primary joists lie in a common horizontal plane;
(d) a plurality of shear connectors anchored to the top flange of the steel beam, said shear connectors being spaced apart and positioned between the first ends of the primary joists;
(e) metal decking overlying and fastened to the primary joists; and (f) concrete topping placed over the metal decking and extending into the space between the first and second flanges of the base track, with the upper surface of the concrete topping being at a selected floor elevation.
44. The wall assembly of Claim 43 wherein at least one of the cutouts in the base track's first flange is configured to receive an open-web steel joist.
45. The wall assembly of Claim 43 wherein at least one of the cutouts in the base track's first flange is configured to receive a channel-shaped joist.
46. The structural subassembly of Claim 43 wherein the upper edge of the base track's second flange coincides with a selected floor elevation.
47. The structural subassembly of Claim 43 wherein:
(a) the base track's second flange has a plurality of joist cutouts;
(b) the subassembly further comprises a plurality of supplementary floor joists, each having a first end disposed within one of the joist cutouts in said second flange, so as to transfer vertical loading to the steel beam, and having a second end supported on a second auxiliary support structure, such that the top surfaces of the supplementary joists lie in the same plane as the primary joists; and (c) the metal decking overlies and is fastened to both the primary and supplementary joists.
(a) the base track's second flange has a plurality of joist cutouts;
(b) the subassembly further comprises a plurality of supplementary floor joists, each having a first end disposed within one of the joist cutouts in said second flange, so as to transfer vertical loading to the steel beam, and having a second end supported on a second auxiliary support structure, such that the top surfaces of the supplementary joists lie in the same plane as the primary joists; and (c) the metal decking overlies and is fastened to both the primary and supplementary joists.
48. The structural subassembly of Claim 43 wherein the first end of at least one of the primary joists bears directly against the inner face of the base track's web member.
49. The structural subassembly of Claim 43 wherein the first end of at least one of the primary joists bears on a joist-support element positioned on the inner face of the base track's web member.
50. The structural subassembly of Claim 49 wherein the joist-support element is a concrete block having a horizontal upper surface with an embedded steel plate.
51. The structural subassembly of Claim 49 wherein the joist-support element is a rectilinear steel tube section.
52. The structural subassembly of Claim 49 wherein the joist-support element is a light-gauge steel channel section with downwardly-disposed flanges and a horizontally-disposed web member.
53. The structural subassembly of Claim 49 wherein the joist-support element is a light-gauge steel channel section with downwardly-disposed flanges and a horizontally-disposed web member, said web member having a steel reinforcing plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002407253A CA2407253C (en) | 2002-10-29 | 2002-10-29 | Fast track building systems |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002407253A CA2407253C (en) | 2002-10-29 | 2002-10-29 | Fast track building systems |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2407253A1 CA2407253A1 (en) | 2004-04-29 |
| CA2407253C true CA2407253C (en) | 2006-09-19 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002407253A Expired - Lifetime CA2407253C (en) | 2002-10-29 | 2002-10-29 | Fast track building systems |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2407253C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008116269A1 (en) * | 2007-03-27 | 2008-10-02 | Australian Tube Mills Pty Limited | Composite and support structures |
| US8230657B2 (en) | 2008-01-24 | 2012-07-31 | Nucor Corporation | Composite joist floor system |
| US8621806B2 (en) | 2008-01-24 | 2014-01-07 | Nucor Corporation | Composite joist floor system |
| US8661755B2 (en) | 2008-01-24 | 2014-03-04 | Nucor Corporation | Composite wall system |
| CN104563351A (en) * | 2013-10-29 | 2015-04-29 | 山东建筑大学 | Floor system combined by building block flat arches |
| JP7185616B2 (en) * | 2017-02-28 | 2022-12-07 | 株式会社竹中工務店 | Steel-framed concrete beam construction method and steel-framed concrete beam design method |
| CN110984640B (en) * | 2019-12-24 | 2021-12-03 | 国网福建省电力有限公司宁德供电公司 | Assembly type substation structure system for pipeline station |
-
2002
- 2002-10-29 CA CA002407253A patent/CA2407253C/en not_active Expired - Lifetime
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| Publication number | Publication date |
|---|---|
| CA2407253A1 (en) | 2004-04-29 |
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