WO2011056897A2

WO2011056897A2 - Building system and method

Info

Publication number: WO2011056897A2
Application number: PCT/US2010/055332
Authority: WO
Inventors: Philip George Ellis; Morgan Jay Ellis
Original assignee: Framemax International Limited, A Hong Kong Limited Liability Company
Priority date: 2009-11-04
Filing date: 2010-11-03
Publication date: 2011-05-12
Also published as: WO2011056897A3

Abstract

A multi-level building system including one or more central cores including at least one of concrete shear walls and structural steel brace frames to resist lateral loads; multiple levels, each level comprising cold-formed-steel load bearing walls; and a floor system surrounding and coupled to the one or more central cores, the floor system including floor joists, decking supported by the floor joists, and at least one of thin concrete slab and reinforced concrete slab over the decking.

Description

BUILDING SYSTEM AND METHOD

FIELD OF THE INVENTION

[01] The field of the invention relates, in general, to residential, commercial, and industrial building systems and methods of construction.

BACKGROUND OF THE INVENTION

[02] Building structures are required to support two primary loads, gravity loads and lateral loads. Gravity loads are essentially vertical loads which include the building's weight, furniture, equipment and occupant loads and special loads like snow, water and sand. Lateral loads are essentially horizontal loads which include wind and seismic forces. Building structures can support these loads in many different ways. Gravity loads are typically supported by load bearing walls or by columns. Floor systems such as concrete slabs, concrete slabs over steel or concrete beams, or concrete slabs over light gauge joists are all common methods of delivering most of the gravity load to the walls and columns. The building elements most often used to resist the lateral loads include shear walls, braced frames and moment frames.

[03] For a typical building framed with cold-formed-steel (CFS, previously referred to in the industry as "light gauge" or "metal studs"), gravity loads are resisted by load bearing walls and lateral loads are resisted by shear walls. The shear walls consist of shear panels (plywood, OSB, sheet metal, or a proprietary product) attached to the load bearing studs with heavy built-up posts and tie-downs at the ends of the shear walls. With this type of building there is typically a very thin slab over metal deck over floor joists at each level. In high seismic zones, the building code limits this type of building to a height of 65-feet since the shear walls are also bearing walls. See Figures 1 , 2 and 3 for examples of this type of building.

[04] For a typical concrete high rise building, gravity loads are resisted by concrete columns and load bearing concrete walls and lateral loads are resisted by solid concrete shear walls which are typically located at the core of the building. The core is considered the section of the building where the elevator and stair shafts occur. This is often at the center of the building so the perimeter of the building is open for better views. With this type of building there is typically a flat concrete slab at each level. This building system typically includes many CFS non-load-bearing walls at each level. In high seismic zones, the building code limits this type of building to a height of 240-feet. See Figures 4, 5 and 6 for examples of this type of building.

SUMMARY OF THE INVENTION

[05] To overcome the above problems and others, an aspect of the invention involves a building system and method that incorporate aspects of each of the above building systems, but in itself, is different from than both of these systems and it will offer many opportunities to make the construction process more efficient. The building system and method utilizes CFS load bearing walls to support the gravity loads and concrete shear wall or structural steel brace frame cores to resist the lateral loads. The floor system includes a thin concrete or reinforced concrete slab over metal or other deck over floor joists at each level. Since the CFS load bearing walls are not resisting lateral forces, the building code allows this building to reach a height of 240-feet. See Figures 7, 8 and 9 for examples of this type of building.

[06] The advantage of this new type of building is that the floors are lighter, which reduces both the total building weight and also the seismic force since the seismic force is directly proportional to the building weight. This system and method also makes use of the CFS walls that are already in the building. By increasing the size and gauge of the CFS studs in these walls, they can become load-bearing instead of non-load- bearing. Since the slab is much lighter and supported by floor joists, there is no need for the shoring of wet concrete that is required in typical concrete buildings. This can improve construction speed and sequencing. Additionally, with this system and method, it is possible to preassemble the load bearing walls into panels or even complete 3D modules offsite with safer, more efficient off-site labor and better quality control. This offsite panelization or modularization will also allow for much faster field erection time. This new type of building system and method is applicable to all building heights.

[07] Another aspect of the invention involves a multi-level building system including one or more central cores including at least one of concrete shear walls and structural steel brace or moment frames to resist lateral loads; multiple levels, each level comprising CFS load bearing walls; and a floor system surrounding and coupled to the one or more central cores, the floor system including floor joists, decking supported by the floor joists, and at least one of thin concrete slab and reinforced concrete slab over the decking.

[08] One or more implementations of the aspect of the invention described immediately above includes one or more of the following: the building system includes more than six levels; the CFS load bearing walls include preassembled panels; and/or the CFS load bearing walls include 3D modules; the cold-formed-steel (CFS) load bearing walls include roll-formed heavy light-gauge steel; the roll-formed heavy light- gauge steel is up to 4.0mm in thickness; and/or the roll-formed heavy light-gauge steel is greater than 1.5mm in thickness.

[09] A further aspect of the invention involves a method of constructing a multi-level building system including constructing a foundation; constructing one or more central cores on the foundation, the one or more central cores including at least one of concrete shear walls and structural steel brace or moment frames to resist lateral loads; constructing multiple levels including installing CFS load bearing walls and non load bearing walls, installing a floor system surrounding the one or more central cores, and coupling the floor system to the one or more central cores, the floor system including floor joists, decking supported by the floor joists, and at least one of thin concrete slab and reinforced concrete slab over the decking.

1. One or more implementations of the aspect of the invention described

immediately above includes one or more of the following: constructing the one or more central cores in advance of constructing the multiple levels; coupling the floor system to the one or more central cores diaphragm collector connections; the CFS load bearing walls and the non load bearing walls are installed to the diaphragm collector

connections; lifting the non load bearing walls into place before the floor joists are set in place and installing the non load bearing walls after the floor joists are set in place;

installing the floor system after the walls are installed; roll forming heavy light-gauge steel to create the cold-formed-steel (CFS) load bearing walls; the roll-formed heavy light-gauge steel is up to 4.0mm in thickness; the roll-formed heavy light-gauge steel is greater than 1.5mm in thickness; and/or pre-processing heavy light-gauge steel flat strip prior to roll-forming the heavy light-gauge steel flat strip. .

BRIEF DESCRIPTION OF THE DRAWINGS

[10] Figure 1 is a perspective view of a cold-formed-steel building system of the prior art;

[1 1] Figure 2 is a top plan view of the cold-formed-steel building system illustrated in Figure 1 ;

[12] Figure 3 is a cross-sectional view of the cold-formed-steel building system illustrated in Figure 1 ;

[13] Figure 4 is a perspective view of a concrete high rise building system of the prior art;

[14] Figure 5 is a top plan view of the concrete high rise building system illustrated in Figure 4;

[15] Figure 6 is a cross-sectional view of the concrete high rise building system illustrated in Figure 4;

[16] Figure 7 is a perspective view of a building system constructed in accordance with an embodiment of the invention;

[17] Figure 8 is a top plan view of the building system illustrated in Figure 7;

[18] Figure 9 is a cross-sectional view of the building system illustrated in Figure 7;

[19] Figure 10 is a junction between an end of a stud and a base plate, or an end of a nog and a stud, of an embodiment of a CFS metal frame assembly; and

[20] Figure 1 1 is a flow diagram of an exemplary CFS method for producing a metal frame assembly.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION

[21] With references to Figures 7-9, a building system 100 and method in accordance with an embodiment of the invention will be described. Although the building system 100 is shown with four floors, this is done to facilitate the reader's understanding of the invention. The building system 100 and method is applicable to all building heights, and is particularly applicable to building heights greater than six (6) stories. [22] The building system 100 includes one or more concrete shear wall cores 105 and a plurality of floors 1 10 built around and connected to the core(s) 105. Each level/floor 1 10 includes a floor system 120 having a thin concrete slab over metal deck over floor joists 120. The floor system 120 of each level/floor 1 10 is connected to the core(s) 105 in any well-known manner. Cold-formed-steel (CFS) load bearing walls 130 support the gravity loads in the building system 100. The size and compressive strength of the CFS studs/supports in the CFS load bearing walls 130 in the lower floors are greater than in the lower floors because the lower CFS load bearing walls 130 support the gravity loads of the upper floors 1 10 (e.g., size and compressive strength increases progressing from the upper floors 1 10 to the lower floors 1 10). The CFS load bearing walls 130 may be preassembled into panels and/or complete 3D modules.

[23] A method of constructing the building system 100 will be generally described. Starting from a concrete foundation or podium 140, one or more concrete/steel cores 105 are constructed. The concrete/steel cores 105 are constructed a few levels in advance of the rest of the load bearing structure. The core(s) 105 will have a diaphragm collector connection at each level. The CFS load bearing walls 130 and non load bearing walls are installed to the diaphragm collector connections. The non load bearing walls can be lifted into place before the floor joists, but do not have to be installed until after the floor joist is set in place. After the walls, the cold-formed-steel joists or floor panels are installed. Floor decking is placed on top of the floor, which can act as a diaphragm or formwork for a poured concrete diaphragm. This diaphragm is tied back into the core or cores through the diaphragm collector connections. The above is repeated for all levels. At the roof, the roof panels are used for the roof diaphragm.

[24] The building system 100 utilizes the CFS load bearing walls 130 to support the gravity loads and the concrete or structural steel shear wall core(s) 105 to resist the lateral loads. Since the CFS load bearing walls 130 are not resisting lateral forces, building codes allow this building to reach a height of 240-feet.

[25] The advantage of the building system 100 and method is that the floors are lighter, which reduces both the total building weight and the seismic force (since the seismic force is directly proportional to the building weight). This system and method also makes use of the CFS walls that are already in the building. By increasing the size and gauge of the CFS studs in the CFS load bearing walls 130, they can become load- bearing instead of non-load-bearing. Since the thin concrete slab in the floor system 1 10 is much lighter than concrete slabs in typical concrete buildings and supported by floor joists, there is no need for the shoring of wet concrete that is required in typical concrete buildings. This can improve construction speed and sequencing. Additionally, with the building system 100 and method, it is possible to preassemble the load bearing walls into panels or even complete 3D modules offsite with safer, more efficient off-site labor and better quality control. This offsite panelization or modularization allows for much faster field erection time.

[26] One or more of the steel framing members (e.g., CFS load bearing wall(s), non load bearing wall(s), panel(s), module(s)) shown and/or described herein may be constructed using the metal frame/frame assembly methods/devices shown and described with reference to Figures 10 and 1 1 below.

[27] Figure 10 shows the connection between the bottom of a stud 20 and a base plate 21. It can be seen that the base plate 21 differs from the stud 20 primarily in having a C-section along its entire length, there being no requirement for the strengthening achieved by rolling to form a C-section. The base plate consists of a U- section.

[28] Individual components of a required frame assembly may be manufactured by use of roll forming apparatus adapted to produce frame members of the desired configuration from galvanised flat steel in coil form. The roll forming apparatus may be portable so as to be located at a construction site. Alternatively, the roll forming apparatus may be located at a central manufacturing site, with information for specific jobs downloaded directly to the apparatus.

[29] An important aspect of the present invention is the ability to accurately roll-form "heavy" light-gauge steel (up to 4.0mm in thickness). Typically, most light-gauge steel is in the 0.5mm to 1.5mm range. Accurately roll-forming "heavy" light-gauge steel (and achieving fast production speeds) is done by first pre-processing the steel flat strip prior to roll-forming. Roll-forming heavier light-gauge steel very accurately is very difficult due to the forces required to roll-form the steel, and, hence, the difficulty is stopping to punch or cut the steel accurately. Accurately roll-forming "heavy" light-gauge steel (and achieving fast production speeds) is important in the present inventor for achieving higher building requirement (i.e., above 6 stories)

[30] A preferred method of producing a building frame assembly of the invention is now described with reference to Figure 1 1.

[31] Data from architectural and structural engineering plans and other sources are processed using specific software to generate a required frame for a particular wall, floor, ceiling or roof frame. This design will include not only the dimensions of the space/frame but also the locations and dimensions of architectural and other features required to be accommodated in the space/frame, such as windows, doors, air- conditioning ducts, electrical sockets and switches and the like. The frame assembly outline is then downloaded via internet link, for example, to the factory site where the rollformer is located. The rollformer computer controls all operations of the rollformer to produce the frame members required for the frame assembly. Prior to roll-forming, the steel flat strip is first pre-processed. The special roll-forming equipment allows for accurate cutting, punching, etc. of "heavy" CFS (cold-formed steel) profiles. The length and configuration or form of each frame member for this frame assembly are calculated by the computer, which in turn controls operation of the special roll-forming equipment to form each required frame member (e.g., "heavy" CFS profiles) from the flat steel coil in a substantially continuous operation.

[32] Thus, by employing the method of the present invention involving the roll forming apparatus described, customized frame assemblies to fit spaces/frames having specified design characteristics can be manufactured and constructed conveniently and efficiently. Effectively a kit set of frame members is provided for each required building frame assembly. This avoids the problems associated with the use of standard preformed steel frame members which must be manually cut, punched and forced together in a manner which often results in the deformation of the smooth surfaces to which cladding must be applied.

[33] Thus, important aspects of the building system 100 and method include CAD design from data from architectural or structural engineering plans; CAM instructions generated from these drawings to control the automated roll-formers; special roll- forming equipment to allow for accurate cutting, punching, etc. of "heavy" CFS (cold- formed steel) profiles; and the above-described building method of combining a concrete core system of restraining lateral loads with a CFS system of supporting the gravity loads of any building.

[34] Where in the foregoing description reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

[35] The above figures may depict exemplary configurations for the invention, which is done to aid in understanding the features and functionality that can be included in the invention. The invention is not restricted to the illustrated architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, although the invention is described above in terms of various exemplary embodiments and implementations, it should be understood that the various features and functionality described in one or more of the individual embodiments with which they are described, but instead can be applied, alone or in some combination, to one or more of the other embodiments of the invention, whether or not such embodiments are described and whether or not such features are presented as being a part of a described embodiment. Thus the breadth and scope of the present invention, especially in any following claims, should not be limited by any of the above-described exemplary embodiments.

[36] Terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term "including" should be read as mean "including, without limitation" or the like; the term "example" is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; and adjectives such as "conventional," "traditional," "standard," "known" and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, a group of items linked with the conjunction "and" should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as "and/or" unless expressly stated otherwise. Similarly, a group of items linked with the conjunction "or" should not be read as requiring mutual exclusivity among that group, but rather should also be read as "and/or" unless expressly stated otherwise. Furthermore, although item, elements or components of the disclosure may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated. The presence of broadening words and phrases such as "one or more," "at least," "but not limited to" or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent.

Claims

CLAIMS We claim:

1. A multi-level building system, comprising: one or more central cores including at least one of concrete shear walls and structural steel brace frames to resist lateral loads;

multiple levels, each level comprising

cold-formed-steel (CFS) load bearing walls;

a floor system surrounding and coupled to the one or more central cores, the floor system including floor joists, decking supported by the floor joists, and at least one of thin concrete slab and reinforced concrete slab over the decking.

2. The building system of claim 1 , wherein the building system includes more than six levels.

3. The building system of claim 1 , wherein the CFS load bearing walls include preassembled panels.

4. The building system of claim 1 , wherein the CFS load bearing walls include 3D modules.

5. The building system of claim 1 , wherein the cold-formed-steel (CFS) load bearing walls include roll-formed heavy light-gauge steel.

6. The building system of claim 5, wherien the roll-formed heavy light-gauge steel is up to 4.0mm in thickness.

7. The building system of claim 5, wherien the roll-formed heavy light-gauge steel is greater than 1.5mm in thickness.

8. A method of constructing a multi-level building system, comprising: constructing a foundation;

constructing one or more central cores on the foundation, the one or more central cores including at least one of concrete shear walls and structural steel brace frames to resist lateral loads;

constructing multiple levels including installing cold-formed-steel (CFS) load bearing walls and non load bearing walls, installing a floor system surrounding the one or more central cores, and coupling the floor system to the one or more central cores, the floor system including floor joists, decking supported by the floor joists, and at least one of thin concrete slab and reinforced concrete slab over the decking.

9. The method of claim 8, further including constructing the one or more central cores in advance of constructing the multiple levels.

10. The method of claim 8, further including coupling the floor system to the one or more central cores diaphragm collector connections.

1 1. The method of claim 10, wherein the CFS load bearing walls and the non load bearing walls are installed to the diaphragm collector connections.

12. The method of claim 8, further including lifting the non load bearing walls into place before the floor joists are set in place and installing the non load bearing walls after the floor joists are set in place.

13. The method of claim 12, further including installing the floor system after the walls are installed.

14. The method of claim 8, further including roll forming heavy light-gauge steel to create the cold-formed-steel (CFS) load bearing walls.

15. The method of claim 14, wherein the roll-formed heavy light-gauge steel is up to 4.0mm in thickness.

16. The method of claim 14, wherein the roll-formed heavy light-gauge steel is greater than 1.5mm in thickness.

17. The method of claim 14, further including pre-processing heavy light-gauge steel flat strip prior to roll-forming the heavy light-gauge steel flat strip.