The invention relates generally to steel framed buildings, and, more specifically to modular components for steel framed buildings.
Steel framed buildings include a steel frame of columns, girders, and beams that support concrete decks. Once installed, the concrete decks form the base of the various floors of the building. Building systems such as walls, facilities components (e.g., electrical, plumbing, and heating, ventilation, and air conditioning (HVAC) components), and equipment are then attached to the concrete deck to finish out the building. In the construction of steel framed buildings, the concrete decks are typically assembled onsite with individual components and without any aggregation of the individual components prior to arriving on the construction site. Variations in onsite assembly techniques, materials, and conditions can lead to inconsistencies in the quality of the finished concrete decks. For example, assembly of concrete decks typically includes mixing and pouring of concrete at the construction site. There are many variables, such as the weather, the quality of the concrete components, and the skill of the people doing the work, which affect the quality of the resulting concrete and which are difficult to control at a construction site.
In addition to the variables involved in onsite assembly of concrete decks for steel framed buildings, other issues related to concrete decks can affect the construction of a steel framed building. For example, the top portion of a full height wall in the interior of a steel framed building is referred to as the “head of wall condition.” The head of wall condition exists at fire, smoke, and/or sound rated walls and because of variations in the design and construction of concrete decks, the head of wall condition needs to be evaluated individually in each steel framed building to ensure that applicable fire, smoke, and/or sound ratings are met. Additionally, the anchoring of building systems, such as interior walls, facilities components, and equipment to concrete decks is typically customized for each individual steel framed building. Further, the onsite customization of anchoring systems does not typically take into account any future needs and/or uses of the steel frame building.
A deck assembly module is disclosed. The deck assembly module can be installed into the steel frame of a steel framed building. The deck assembly module includes a cellular metal deck. In an embodiment, the cellular metal deck includes a bottom plate having a top major surface and a bottom major surface, an angled decking sheet, and fireproof insulation. The angled decking sheet is angled to form a repeating pattern of troughs and peaks, the angled decking is adjacent to the top major surface of the bottom plate, and the fireproof insulation is located in channels formed by the peaks of the angled decking sheet and the top surface of the bottom plate and the angled decking sheet. The deck assembly module may also include a concrete portion that includes a top major surface, referred to as a concrete deck. The concrete for the concrete portion of the deck assembly module can be poured into the cellular metal deck in an offsite assembly facility or the concrete portion of the deck assembly module can be mixed and poured into the cellular metal deck at or near the construction site.
Other aspects and advantages of embodiments of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrated by way of example of the principles of the invention.
a highlights a mid-bay in the steel frame of
b highlights two end-bays in the steel frame of
a-3i depict plan, side, and perspective views of various embodiments of a cellular metal deck.
a-4f depict plan, side, and perspective views of a cellular metal deck with a closure frame at the perimeter of a cellular metal deck.
a-5f depict plan, side, and perspective views of a support structures and a cellular metal deck with support structures in a grid pattern.
a-6r depict plan, side, and perspective views of void structures and a cellular metal deck with various embodiments of void structures.
a-7o depict plan, side, and perspective views of reinforcing structures and a cellular metal deck with various embodiments of reinforcing structures.
a-8f depict plan, side, and perspective views of a deck assembly module that includes a cellular metal deck as described with reference to
a-9i depict plan, side, and perspective views of attachment elements and a deck assembly module that includes attachment elements in a grid pattern at the surface of the concrete deck.
a depicts a cellular metal deck as described above with reference to
b depicts a deck assembly module that includes building systems attached at the bottom surface of the cellular metal deck and attached at the top surface of the concrete.
c depicts a perspective view of a deck assembly module that includes building systems attached at the bottom surface of the cellular metal deck and attached at the top surface of the concrete.
a is an expanded sectional view of a deck assembly module relative to a steel frame of a steel framed building and building systems that are attached to the top and bottom surfaces of the deck assembly module.
b is a perspective view of two separate deck assembly modules installed in the steel frame of a steel framed building.
c depicts a side view of an embodiment of a deck assembly module in which the perimeter of the deck assembly module includes an angled flange.
d depicts a perspective view of a deck assembly module as described above relative to the steel frame of a steel frame building.
Throughout the description, similar reference numbers may be used to identify similar elements. Additionally, in some cases, reference numbers are not repeated in each figure in order to preserve the clarity and avoid cluttering of the figures.
It will be readily understood that the components of the embodiments as generally described herein and illustrated in the appended figures could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by this detailed description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment. Thus, discussions of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.
Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.
Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment. Thus, the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
In an embodiment, a deck assembly module is disclosed. The deck assembly module can be installed into the steel frame of a steel framed building. The deck assembly module includes a cellular metal deck and may include a concrete portion that includes a top major surface, referred to as a concrete deck. The concrete for the concrete portion of the deck assembly module can be poured into the cellular metal deck in an offsite assembly facility or the concrete portion of the deck assembly module can be mixed and poured into the cellular metal deck at or near the construction site.
In either case, the deck assembly module can be assembled prior to being installed into the steel frame of a steel framed building. A deck assembly module as described in detail below can be fabricated to fit within the steel frame of a steel framed building, the deck assembly module can be designed to reduce the combined floor and beam system dimensions, the deck assembly module exhibits a reduced weight, and the deck assembly module may include attachment elements that provide for easy attachment of various building systems at an array of locations.
In the embodiment of
In the embodiment of
The spacing of the girders 14 is dictated by the spacing of the columns 12. The spacing of the beams 16 is more flexible. In an embodiment, beams are located between pairs of columns and additional beams are located between columns. In an embodiment, beams are spaced apart by about 10 feet, although other spacing is possible. As will be described below, the spacing of the columns, girders, and beams forms “bays,” where a bay is generally defined as the area bordered by a pair of parallel girders and a pair of parallel beams. The dimensions of the bays may be the same from bay-to-bay or may vary depending on the building. In an embodiment, some of the bays in a building have similar dimensions while other bays of the building have dimensions that are customized to correspond to specific features of the building. As is described below, the deck assembly modules are sized such that a deck assembly module fills a bay. The shape of a bay may vary depending on whether the bay is a mid-bay or an end-bay, where a mid-bay is bordered by girders and beams but does not include any column connection points and an end-bay includes at least one column connection point.
In an embodiment, each deck assembly module is configured to have a shape that corresponds to the shape of the bays that are formed by the steel frame 10. For example, deck assembly modules intended for the mid-bays 20 are shaped to correspond to the shape of the mid-bays and deck assembly modules intended for the end-bays 22 are shaped to correspond to the shape of the end-bays. Additionally, deck assembly modules that are intended for end-bays are shaped to correspond to the particular location of the columns. For example, the two corners of a deck assembly module that will abut to a column are dependent on the location of the deck assembly module relative to the columns. With reference to
In an embodiment, the exact size and shape of the deck assembly module is governed in part by at least one of the following parameters: structural performance requirements of the steel frame 10; the framing geometry of the steel frame; transportation requirements of the jurisdictions in which the deck assembly module is transported on public roads; and vehicle availability for transport. In an embodiment, the deck assembly module is designed with a 10′-0″ maximum width dimension and a fifty foot maximum length dimension so that the deck assembly module can be transported as one piece on public roads using conventional transportation means. In another embodiment, the deck assembly module is designed with a 15′-0″ maximum width dimension and a fifty foot maximum length dimension, although it should be understood that other dimensions are possible.
Embodiments of a deck assembly module are now described in detail with respect to
In the embodiments of
In the embodiments of
With reference to
In an embodiment, the angled decking sheet 36 is attached to a bottom plate, which is a metal plate that has a top major surface and a bottom major surface. The angled decking sheet is attached to the bottom plate such that metal channels or tubes are formed in the areas of the troughs. Fireproof insulation is located within the metal channels to produce a fire rated deck assembly.
e depicts a plan view of the angled metal sheets 36 before the sheets are attached to each other.
h depicts a plan view of a cellular metal deck 50 in which the angled decking sheets of
In an embodiment, the sides of the angled metal sheets 36 are configured to receive a closure strip 52 (see
In an embodiment, the cellular metal deck 50 includes a closure frame that is located around the perimeter of the cellular metal deck. The closure frame includes a perimeter wall that gives the cellular metal deck more structural integrity for transport and for attachment to the steel frame of a steel framed building. The closure frame may also extend above the peaks of the angled decking sheet to provide forming for the concrete that will be poured on top of the cellular metal deck. Although the closure frame may extend above the peaks of the angled decking sheet, in other embodiments, the closure frame does not extend above the peaks of the angled decking sheet. The closure frame can be made in various shapes and sizes. In an embodiment, the material utilized for the closure frame is galvanized or stainless structural steel. The material used to make the closure frame will typically come from a steel mill at various lengths and will then be joined together by traditional methods of welding, complying with ANSI/AWS D1.1/D1.1M:2010, or using a splice plate(s) and bolt(s) and nut connections.
Specific material quality requirements for the angled metal sheet 36, the closure strip 52, and the closure frame 54 can be found, for example, in the Applicable ASTM Specifications for Various Structural Shapes, Table 2, in the material qualities as described in Designing with Structural Steel, A guide for Architects, by the American Institute of Steel Construction, 2002.
An embodiment of a closure frame 54 is described with reference to
The closure frame is attached to the perimeter of the cellular metal deck 50 by, for example, welding or fastening.
In an embodiment, the cellular metal deck 50 includes support elements that are located in the channels 42 formed by the troughs 38 of the angled metal sheet.
The support elements may be spaced apart from each other in a grid pattern, in which the grid pattern is predefined before the deck assembly is installed into a steel frame of a steel framed building. In an embodiment, the support elements are used to support void structures and also serve as attachment elements for attaching building system to the underside of the deck assembly module.
a depicts a plan view of support elements 58 spaced in a grid pattern that is applicable to the cellular metal deck 50 as described with reference to
d depicts a plan view of the cellular metal deck 50 that includes the support elements 58 of
In an embodiment, the support elements 58 are internally threaded cylinders, which are accessible from the bottom major surface of the bottom plate 46 of the cellular metal deck 50 and which act dually as a support to a void structure that is connected to re-bar above and as an attachment point for building systems that are hung from the bottom side of the deck assembly module. In this embodiment, each support element is multi-functional by being both a support spacer to the void structure connected to the reinforcing bars and a threaded insert that forms the basis of an attachment feature. Traditionally, attachment features are individually installed below the deck at the required anchorage points on an as needed basis after the deck is affixed within the steel frame. For example, holes are drilled in the underside of the deck assembly and metal threaded attachment elements are hammered into the drilled holes. In accordance with an embodiment of the invention, the support elements are installed in a predefined known pattern on the cellular metal deck as part of the deck assembly process. For example, the support elements are centered in the channels formed by the troughs and spaced anywhere from one foot apart in a row to as far as two feet apart depending on the specific design requirements of the steel framed building. Because the support elements are preinstalled and accessible from the bottom major surface of the bottom plate, the deck assembly module includes an inherent attachment system that can be taken advantage of in the building design process. In an embodiment, the use of support elements as described with reference to
In an embodiment, the deck assembly module 30 includes at least one void structure that creates a barrier to concrete in order to displace concrete. A void structure is used to displace a volume of concrete with a lighter material (e.g., air) to reduce the weight of the deck assembly module without compromising the structural integrity of the deck assembly module. Typical aggregate concrete has an average weight of 150 pounds per cubic foot or 125 pounds per cubic foot with lightweight aggregate. The use of the void structure can reduce the volume of concrete in the deck assembly module by at least 10% and potentially by as much as 50% of the volume of concrete based on the individual design requirements of the building's structure. In an embodiment, the void structure is made of a lightweight material such as cardboard and creates air pockets such that the volume of the void structure is filled with air instead of concrete. The void structure can be of any shape, including for example, circular, polygonal, triangular, square, pentagonal, hexagonal etc. In an embodiment, the void structure is designed to maximize the volume of the corresponding void relative to the volume of concrete while still meeting the required performance criteria of the deck assembly module. In an embodiment, the void structures are elongated circular or rectangular cardboard tubes having circular or rectangular cross-sections. Alternatively, the void structures can be made of other materials that can be configured to create voids of similar sized shapes and volumes. The use of cardboard void structures may also provide advantages that include the ability to be more ecologically sensitive by both using less concrete, which is energy intensive to make, and the use of recycled paper material for the void structures. In an embodiment, a void structure made by SONO TUBE may be used. In an embodiment, the void structures form voids of at least 2″ and as large as 12″. The use of a tube in a bidirectional arrangement can be achieved by cutting half of the diameter in the width of a circular void structure on one circular void structure and a corresponding mitering on another circular void structure, similar to how logs for a log cabin are mitered.
a depicts a plan view of a unidirectional layout of void structures 60, which are circular void structures laid out in a parallel pattern in spacing that corresponds to the spacing of the troughs 38 of the angled metal sheets 36 of
d depicts a plan view of a bidirectional layout of void structures 60, which are circular void structures laid out in a parallel grid pattern in spacing that corresponds to the spacing of the channels 42 formed by the troughs 38 of the angled metal sheet 36 of
g depicts a plan view of a unidirectional layout of void structures 60, which are rectangular void structures laid out in a parallel pattern in spacing that corresponds to the spacing of the channels 42 formed by the troughs 38 of the angled metal sheet 36.
j depicts a plan view of a bidirectional layout of void structures 60, which are rectangular void structures laid out in a parallel grid pattern in spacing that corresponds to the spacing of the channels 42 formed by the troughs 38 of the angled metal sheet 36.
m depicts a plan view of the cellular metal deck 50 that includes a unidirectional layout of circular void structures 60 that are located in the channels formed by the troughs of the angled metal sheet 36.
p depicts a plan view of the cellular metal deck 50 that includes a bidirectional layout of circular void structures 60 that are located in the channels 42 formed by the troughs 38 of the angled metal sheet 36.
In an embodiment, the concrete of the deck assembly module is reinforced with a reinforcing structure such as reinforcing bars “rebar” or welded wire fabric. In an embodiment, the reinforcing structure is configured to comply with American Concrete Institute, ACI, specifications and other applicable building code requirements.
In an embodiment, the reinforcing structure is configured in a grid pattern. For example, the grid pattern may correspond to the channels 42 and 44 formed by the repeating pattern of troughs 38 and peaks 40 of the angled decking sheet 36. In an embodiment, the reinforcing structure is a grid pattern of rebar in which some of the rebar is parallel to the channels formed by the troughs and peaks of the angled decking sheet and some of the rebar is perpendicular to the channels formed by the troughs and peaks of the angled decking sheet. The rebar sits directly on top of the void structure shown in
a depicts a plan view of a rebar reinforcing structure 62 in a grid pattern having spacing that corresponds to the spacing of the channels 42 formed by the troughs 38 of the angled metal sheet 36.
d depicts a plan view of the cellular metal deck 50 that includes the rebar reinforcing structure 62 of
g depicts a plan view of the cellular metal deck 50 that includes the rebar reinforcing structure 62 of
In an alternative embodiment, the deck assembly module 30 does not include a void structure.
m-7o depict an embodiment of the cellular metal deck 50 without a void structure but with the support elements 58.
In the embodiments of
The cellular metal deck 50 described with reference to
Once the cellular metal deck 50 is assembled, concrete is applied to produce the concrete deck 32 of the finished deck assembly module 30. The concrete can be applied to the cellular deck assembly in an offsite facility or on the construction site. If the concrete is applied in an offsite facility, the completed deck assembly module is transported to the construction site as a single piece and if the concrete is applied to the cellular metal deck at the construction site, the cellular metal deck is transported to the construction site without the concrete. Concrete is then mixed and poured onto the cellular metal deck at the construction site.
When applied at the construction site, the concrete is prepared by mixing the proper ingredients in the appropriate proportions to provide the performance needed and then the prepared concrete is poured onto the cellular metal deck as a wet mix. An advantage of applying the concrete at the construction site is a savings in transportation resources that results from transporting less weight and less volume of material. Advantages of applying the concrete in a controlled factory environment include: factory manufactured and applied concrete is often a better quality product because the concrete is mixed in a controlled environment and not exposed to environmental extremes; the concrete can be mixed with better quality control for the pour than in the field; and the pour operation does not have to account for the delivery time that may be involved in using a concrete mixing truck that mixes concrete at a concrete plant and then travels to the construction site to pour the concrete. In an alternative embodiment, a material other than concrete can be used to fill the volume of the deck assembly module.
a depicts a plan view of the deck assembly module 30 after the concrete deck 32 has been added to the cellular metal deck of
d depicts a plan view of the deck assembly module 30 after the concrete deck 32 has been added to the cellular metal deck 50 of
In an embodiment, the deck assembly module 30 includes attachment elements that are accessible from the top major surface of the concrete. For example, the deck assembly module includes a predefined grid pattern of screw attachment inserts that are set in the concrete during or shortly after the pour or that are inserted into the concrete after the concrete has cured but before the deck assembly module has been installed into the steel frame of a steel framed building. In an embodiment, the attachment elements are spaced in a predefined grid pattern of equal intervals, where the intervals correspond to specific design requirements of the steel framed building. For example, the equal spacing intervals of the attachment elements can be from four inches to one foot. Installing attachment elements in a predefined pattern can facilitate independent design requirements to assemble components of a newly constructed steel framed building. Additionally, the attachment elements can be utilized to adapt the building to changes during the building's lifecycle. In an embodiment, the attachment elements are solid tapered and internally threaded cylinders, to which building system such as walls can be attached. In alternative embodiments, other attachment elements may be used.
a depicts a plan view of the attachment elements 64 spaced in a grid pattern that is applicable to the plan views of the cellular metal deck 50 and the deck assembly module 30 as described above.
d depicts a plan view of the deck assembly module 30 that includes the attachment elements 64 distributed in the predefined grid pattern of
In another embodiment, the attachment elements can be a channel track that is set within the concrete and covered with a cap that can be removed on an as needed basis. For example, a 1″ unistrut embed channel can be embedded within the concrete in a predefined pattern, such as a grid pattern with equal spacing. The locations of the channel track can correspond to the specific design requirements of the steel frame building design criteria and can vary from, for example, four inches to one foot apart on center.
g depicts a plan view of the attachment elements 64 in the form of a unistrut embed channel spaced in a grid pattern that is applicable to the plan views of the cellular metal deck 50 and the deck assembly module 30 as described above.
Once the deck assembly module 30 as described above is completed, it is inspected before being installed into the steel frame 10 of a steel framed building. For example, the deck assembly module is inspected upon arrival at the construction site to ensure that no damage has occurred to the deck assembly module during transport. The inspection can be done through conventional methods and should comply with all local, state, and federal requirements. Upon passing inspection, the deck assembly module is installed into the steel frame of a steel framed building. For example, the deck assembly module can be transferred from a delivery vehicle directly to the steel frame of a steel framed building.
The deck assembly module 30 can be placed into a bay and connected to the steel frame 10 of a steel framed building using conventional techniques. In an embodiment, the deck assembly module enables building system equipment, including but not limited to architectural, structural, mechanical, electrical, and/or plumbing components to be connected to the attachment elements on the top and bottom sides of the deck assembly module without having to drill into the deck assembly module and without having to modify the design of the deck assembly module before the deck assembly module is installed into the steel frame of the steel framed building. In an embodiment, the concrete deck 32 can be poured after the cellular metal deck 50 is installed into the steel frame of a steel framed building.
Typically, building systems are attached to the deck of a steel framed building after the deck is installed in the metal frame of a steel framed building. In an embodiment, building systems are attached to the deck assembly module before the deck assembly module is installed into the steel frame of the steel framed building. Attaching various building systems to the deck assembly module described above before installing the deck assembly module into the steel frame of the steel framed building can significantly improve the timing of the traditional placement of such building systems.
a depicts a cellular metal deck 50 as described above with reference to
b depicts a deck assembly module 30 as described above with reference to
c depicts a perspective view of a deck assembly module 30 as described above with reference to
a is an expanded sectional view of the deck assembly module 30, relative to the steel frame (beam 16) of a steel framed building, and building systems 70 and 72 that are attached at the top and bottom surfaces of the deck assembly module. The deck assembly module is the same as or similar to the deck assembly modules described above with reference to
b is a perspective view of two separate deck assembly modules 30 installed in the steel frame 10 (including columns 12, girders 14, and beams 16) of a steel framed building. The deck assembly modules are the same as or similar to the deck assembly modules described above in
In an embodiment, the deck assembly modules 30 are designed so that the deck assembly modules do not sit entirely above the top plane of the top flange of the beams and girders.
d depicts a perspective view of a deck assembly module 30 as described above relative to the steel frame 10 (including girders 14 and beams 16) of a steel frame building.
Various embodiments of a deck assembly module 30 have been described above. The deck assembly module provides an intelligent customizable modular steel and concrete deck, which may include integrated attachment elements. The deck assembly module can be filled with concrete at the building site where building construction occurs or the deck assembly module can be filled with concrete at a remote pre-fabrication facility. Both options enable installation of building systems prior to the deck assembly module being installed into the steel frame of a steel framed building. An embodiment of the deck assembly module may provide benefits in the construction of steel framed buildings such as: a modular assembly that fits within the steel frame of a steel framed building; a reduced combined floor and beam system dimension because the deck assembly module sits at least partially below the top flange of the beams; similar or greater volume of floor design with a reduced weight through the use of void structures; and a predetermined attachment system that provides predefined connection points on the bottom and top surfaces of the deck assembly module.
In an embodiment, instances of roof construction may not require concrete or re-bar. Roofing requirements may be building specific and the above described cellular metal deck 50 can be utilized as a component for the roof level of a steel framed building, minus the flooring material (e.g., the concrete).
In the above description, specific details of various embodiments are provided. However, some embodiments may be practiced with less than all of these specific details. In other instances, certain methods, procedures, components, structures, and/or functions are described in no more detail than to enable the various embodiments of the invention, for the sake of brevity and clarity.
Although specific embodiments of the invention have been described and illustrated, the invention is not to be limited to the specific forms or arrangements of parts so described and illustrated. The scope of the invention is to be defined by the claims appended hereto and their equivalents.
This application is entitled to the benefit of provisional U.S. patent application Ser. No. 61/346,812, filed May 20, 2010, which is incorporated by reference herein.
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