Assembly Module for Composite Wall and Method of Assembly
Systems and methods for constructing composite wall structures are described in which opposing faceplates are provided that define a transverse void. A plurality of through connector assemblies, which span the transverse void between the faceplates, are attached with the opposing faceplate. A connecting mechanism is applied to the through connector assemblies from an outside of at least one of the faceplates and attaches with portions of the through connector assemblies in the transverse void. The transverse void may be filled with a fill material after attaching the opposing faceplates with the plurality of through connector assemblies.
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The present subject matter is directed to assembly modules for composite walls, and methods for constructing composite walls. The present subject matter is applicable to various forms of modular composite construction and finds particular applicability in the construction of steel-plate-concrete (SC) wall systems.
Conventional concrete walls systems typically use reinforcing steel (rebar) within the concrete wall to improve the structural characteristics of the concrete. However, in construction applications where accelerated construction of large structures is desired, the intricacies of such construction techniques can prove to be inefficient for a number of reasons, including the amount of time to assemble/disassemble formwork and place rebar, as well as the associated requirement for significant on-site activities.
SC modular walls, and other modularized construction assemblies, are experiencing increasingly widespread use in various construction applications, including, for example, the construction of nuclear power plants. The safe and rapid construction of nuclear power plants has become a particularly critical concern with respect to providing alternative energy in countries around the world, including the United States.
Known systems for SC construction may include the use of internal framing that is welded to opposing plates. For example, a Bi-Steel process is known for use in certain applications using friction welded tie bars. Such methods may include using faceplates with a thickness between 5 to 20 millimeters, and a distance between the plates of 200 to 700 millimeters. Other structures may also use a welded internal frame that is in turn welded to the external plates.
However, known systems that rely on welding of the internal support framework do not satisfy all of the needs of current applications, including, for example, size requirements, structural integrity and efficiency of construction. Of particular concern are the requirements for skilled labor to perform the difficult, and/or intricate, field or shop welding procedures in a large scale construction project. These factors can quickly become prohibitive and/or greatly increase the cost and time of construction. Usage of large scale welding can also lead to warping and residual stresses, factors that can affect the structure's strength and function.
In order to effectively build large structures, such as new nuclear power plants, in a timely manner, it is becoming increasingly important to reduce the high labor cost and lengthy schedules typically associated with nuclear power plant construction. Such improvements are necessary in order to allow nuclear power to become a more viable alternative to fossil fuels and other lower capacity alternative fuel sources.
Additionally, since construction of nuclear plants, and other large concrete structures, including nuclear waste processing/storage facilities and other structures such as chemical weapons demilitarization facilities that are designed for blast and missile resistance, involve substantial reinforcing, concrete and other on-site activities, concerns must be addressed regarding the shortages of skilled on-site construction labor and the associated higher costs that would be experienced with simultaneous construction of multiple large projects.
The present subject matter provides improvements in the use of modular structural assemblies that may provide efficiencies, including simplified construction, cost savings, and structural integrity, in the construction of SC modular walls, and similar applications, that may benefit from the use of prefabricated assembly modules in the construction of structures including composite walls, and the like.
SUMMARY OF THE INVENTIONThe present subject matter includes systems and methods for constructing composite walls in a building including the preassembly of wall assembly modules that include opposing faceplates and a plurality of through connector assemblies that attach with the faceplates. In embodiments, opposing faceplates may be attached with a plurality of through connector assemblies that span a transverse void between the faceplates, and may include applying the connecting mechanism from an outside of at least one of the faceplates to attach with a portion of the through connector assembly. Through the use of applying mechanical fastening mechanisms from an outside of a faceplate, several advantages can be achieved such as simplifying assembly, and limiting or avoiding the amount of work required in the transverse void. An assembled wall module may be transported to a construction site, and filled with a fill material. Filling of the assembly module may be done at a position in which the assembly module will occupy in a finished building.
In embodiments, a tension of a connector assembly may be adjusted as part of the assembly process of the assembly module, on-site before filling the assembly module with the fill material, and/or any time after the assembly module is filled with the fill material. Such features may provide advantages over other known systems, such as those that use conventional reinforced concrete construction, or other modular composite construction where internal frames are welded to faceplates.
In embodiments, an external connector may be attached with a through connector assembly on a side of the composite wall. Such external connectors may include baseplates and other structural devices used to distribute or support a load on the wall.
Embodiments may include engaging a connector assembly with a faceplate, such as by a male threaded portion of a connector assembly with a female threaded portion of a hole in at least one of the faceplates.
Embodiments may include placing a plurality of sleeves between opposing faceplates and inserting rods through the sleeves. This may include inserting the rods through a hole in one of the opposing faceplates, through the respective sleeve, and out of a hole in the other of the opposing faceplates. In other embodiments, a plurality of rods and/or sleeves may be fixedly attached to a first faceplate, and a second faceplate positioned with respect to the fixedly attached rods and/or sleeves.
Embodiments may include securing the rods and/or sleeves from an outside of at least one of the opposing faceplates.
Embodiments may include an assembly module for a composite wall, the assembly module including opposing faceplates with a transverse void between the faceplates. A plurality of though connector assemblies at least partially spanning the transverse void may be included. The through connector assemblies may be connected with at least one of the opposing faceplates, and include a securing mechanism that is configured to attach a portion of the through connector assembly at least partially in the transverse void with the at least one faceplate from an outside of the at least one faceplate.
Embodiments may include an intermediate plate positioned between the opposing faceplates and connected with at least one of the through connector assemblies.
In embodiments, the securing mechanism is a mechanical device such as, for example, complementary male and female threaded members, friction secured members, and the like. As described herein, mechanical connections include mechanisms that do not rely on a welding bond for their primary attachment. However, these mechanisms may include incidental welding to facilitate module assembly, and the like.
In embodiments, a threaded portion of the connector assembly may protrude through holes in each of the opposing faceplates and be secured by nuts attached to the threaded portion of the connector assembly. Embodiments may include a second nut configured to be attached to the threaded portion of the through connector.
In embodiments, at least one of the through connector assemblies may include a sleeve between the opposing faceplates. Such sleeves may span a distance between the opposing faceplates, span a distance between one of the faceplates and an intermediate plate, or span a portion of a distance between opposing faceplates.
In embodiments, at least one of the through connectors assemblies may partially penetrate at least one of the faceplates and include a stopping mechanism at an end of the through connector assembly that positions the connector assembly with respect to the faceplate.
Stopping mechanisms may include, for example, a portion of the connector assembly with a larger diameter, a nut attached to a threaded portion of the through connector assembly, a collar on the sleeve, and the like.
In embodiments, at least one of the through connector assemblies may include a sleeve with a female threaded portion and at least one of the opposing faceplates may include a hole substantially where at least one through connector assembly connects with the at least one faceplate. The securing mechanism may include a bolt configured to be inserted through the hole in the faceplate and engaged with the female portion of the sleeve and optionally with the female threads in the faceplate.
In embodiments, the through connector assemblies may include rods or sleeves that traverse the transverse void.
In embodiments, the securing mechanism may be adjustable from an outside of the assembly module after the securing mechanism is secured.
In embodiments, the faceplates may include, or be substantially formed from, sheets of material including through holes, and the securing mechanism may be configured to attach with a portion of the through connector assembly through the holes. In embodiments, faceplates may be formed from at least two plates that are held together and/or compressed via a securing mechanism on one end of a through connector assembly.
In embodiments, the through connectors may be mechanically attached with the faceplates substantially without welding of the through connectors to the faceplates.
In embodiments, the transverse void may have a width greater than 28 inches. Although smaller widths are also envisioned, there are advantages derived from the disclosed structures and methods that are particularly beneficial with respect to known methods in constructing walls with widths greater than 29 inches.
In embodiments where a through connector assembly includes a rod housed within a sleeve, a clearance between the rod and the sleeve may be in a range of 1/64th of an inch to ⅛th of an inch. In other embodiments, this range may be between 1/32nd of an inch and ⅛th of an inch. In other embodiments, this range may be between 1/16th of an inch and ⅛th of an inch.
The enumerated ranges have been found to provide different benefits and tolerances with respect to assembly procedures of the rods and sleeves, as well as the assembly module itself. For example, by minimizing the clearance of the rod within the sleeve, the slip distance will be accordingly smaller once the slip resistance of a pretensioned joint is overcome. However, in situations where manufacturing tolerances require accommodation for variation in the respective bore size and diameter, larger tolerances may be required, such as, for example, 1/16th of an inch to ⅛th of an inch. This may increase an efficiency of the assembly process by minimizing the need for replacement and/or forceable assembly procedures.
Embodiments may include a concrete fill material that substantially fills a transverse void in the assembly module. As used to herein, the transverse void should be understood as the space between opposing faceplates, even in circumstances where the space is filled with a fill material. In embodiments, the faceplates may consist essentially of steel plate material.
Embodiments may include means for connecting the faceplates across the transverse void, and means for adjusting a tension of said means for connecting after the transverse void is filled with a fill material. Embodiments may include means for adjusting a tension of said means for connecting before the transverse void is filled with the fill material. Embodiments may include means for transmitting an attachment load from an exterior portion of one faceplate to an exterior portion of an opposite faceplate.
Embodiments may include means for reducing a stress concentration of an attachment load from an exterior portion of one faceplate.
Further advantages of the present subject matter will be apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of preferred embodiments.
The following detailed description is provided with reference to exemplary embodiments for the ease of description and understanding. Applicants' invention is not limited to the disclosed embodiments, and encompasses other variations that fall within the overall scope of description provided herein.
The following exemplary method is described with reference to
In embodiments, the opposing faceplates may be vertically positioned and secured for assembly. In other embodiments, a first faceplate may be laid horizontally for assembly before positioning the second faceplate. After the one or more plates are positioned in S1100, the method may proceed with S1200.
In S1200, portions of connector assemblies may be positioned with respect to faceplates that have been positioned in S1100. This may include, for example, positioning sleeves, rods, and the like, between two vertically positioned faceplates. Alternatively, but not exclusively, individual sleeves, rods, and the like, may be positioned with respect to a horizontally placed faceplate. In general, connector assemblies may include, for example, combinations of sleeves, rods, and the like, positioned between opposing faceplates and/or intermediate plates between the faceplates.
After a plurality of the portions of the connector assemblies are positioned with respect to the plates, the method may continue with S1300.
In S1300, portions of the connector assemblies that have been positioned may be secured to one or more faceplates, and/or intermediate plates. Various configurations for the securing mechanisms will be described further below. By way of example, in circumstances where two opposing faceplates are positioned vertically, with sleeves for the connector assemblies placed between the faceplates, and rods running through the sleeves and holes in the opposing faceplates, the rods may be secured to an outer portion of the faceplates by attaching, for example, a nut to a threaded end of the rods. It should be noted that embodiments may include where particular connector assemblies are configured to be secured with differently configured mechanisms at opposite ends. For example, one end of a through connector assembly may receive a bolt through the faceplate, whereas the opposite end of the through connector assembly may be engaged with the opposite faceplate, and/or a nut external to the faceplate, via threading on the connector assembly hole in the opposite faceplate, and/or the nut. Alternative securing means may be beneficial in circumstances where the assembly process is different for different sides of the assembly module, for example, if the first faceplate is assembled with the through connector assembly in a horizontal position, it may be advantageous to use methods in which the through connector assembly is fixedly engaged with the faceplate itself, whereas the second faceplate may be attached though a more expedient method that only involves turning an accessible portion of the connector assembly, e.g., a bolt through the second faceplate.
In embodiments, a connecting mechanism may be applied from an outside of at least one of the faceplates to attach with portions of the through connector assemblies that are at least partially in the transverse void. As discussed herein, through connector assemblies may include portions, contiguous or non contiguous, that traverse, or partially traverse, the transverse void, as well as portions that extend partially, or fully, through one or more through holes in faceplates and intermediate plates. Connecting mechanisms described herein may be advantageous in assembly processes by reducing the amount of work that needs to be done in the transverse void, as well as allowing for adjustments in tension of the through connector assemblies. For example, during S1300, a pre-tensioning of the through connector assembly may be accomplished, for example, by adjusting a thread engagement of a securing mechanism. The appropriate amount of pretensioning can vary significantly depending on factors such as, for example, the diameter and material of the bolts, and structural characteristics of securing mechanisms, etc. Pretensioning the assembly may be advantageous in the circumstance where the assembly module is transported and/or lifted prior to placement and filling.
In embodiments where the through connector assemblies are first secured to a first faceplate, such as in a horizontal orientation, a second faceplate, or intermediate plate may be positioned after securing the connectors to the first faceplate. For example, a second faceplate may be positioned according to a subset of the plurality of through connector assemblies, such as on the four corners, that are configured to extend beyond the rest of the attached through connector assemblies. This may be done by extending internal rods or external sleeves, or elongated collars, beyond the length of the rest of the through connector assemblies. By using the subset of the through connector assemblies, the second plate may be accurately positioned without having to perfectly align all of the through connector assemblies with corresponding holes. After the second plate is properly positioned with respect to the subset of through connector assemblies, the remaining through connector assemblies may be individually adjusted, if needed, with respect to the corresponding through hole in the second plate.
After sufficient connections are made between the opposing faceplates, any intermediate plates, and/or the plurality of through connector assemblies, the method may continue to S1400.
In S1400, the assembly module may be positioned in a location for filling. This may include, for example, transporting the module from an assembly location to a worksite where a building is being manufactured. In a preferred embodiment, the module may be placed in a position substantially where it will be located in the completed structure. In embodiments, the module may be connected with other assembly modules prior to, or after, filling. In embodiments, end plates may be provided to allow for the independent filling of the individual assembly module. This may be done as part of an initial assembly process, or it may be performed at the on-site location.
During S1400, a tension of at least one of the through connector assemblies may be checked and/or adjusted to accommodate a desired pre-fill tension. This may allow for different tensions for transport and filling of the assembly module. After the assembly module is positioned for purposes of filling and any desired pre-tensioning is performed, the method may continue with S1500.
In S1500, the assembly module may be filled with a fill material. Examples of appropriate fill material may include, for example, concrete, and the like, such as, self-consolidating concrete, green concrete consisting of cement substitutes, fiber-reinforced concrete, etc. In embodiments that address the requirements of nuclear power facilities, concrete may be used to provide sufficient radiation shielding, and structural integrity that will withstand heat, force and other requirements of such specialized applications. After the assembly module is filled, or partially filled, the method may continue with S1600.
In S1600, a post-tensioning of the connector assemblies may be performed. This may be done, for example, after filling at least a portion of the transverse void with the fill material. In embodiments, the through connector assemblies may be post-tensioned after concrete has cured and gained its sufficient strength to sustain post-tensioning stresses. Such post-tensioning can reduce concrete cracking, especially under severe loads (e.g. earthquake induced loads) and improve the wall strength.
In addition to the above processes, it is an advantage of aspects of the disclosed subject matter that, according to embodiments, an external connector may be easily connected via exemplary through connector assemblies. Thus, an external connection may be made before, during, or after filling of the assembly module. For example, aspects of the present subject matter provide an easy way to add attachments to a composite wall, after filling of the wall, by completely or partially removing an external connector from the wall, that is connected with a through connector assembly, and attaching an external connector to the through connector assembly. For example, in embodiments that use a through rod that penetrates the faceplate and engages with a through connector assembly, the nut(s) at the rod end may be removed, a base plate placed on the faceplate, and the nuts restored. Such methods are easily accomplished, and provide improved structural integrity that is built into the wall and through the wall. They also eliminate the need for direct welded attachment to an individual faceplate or need for drilling new holes in the same to install anchor bolts.
Such mechanisms that attach an external connector to a through connector assembly may provide, for example, means for transmitting an attachment load from an exterior portion of one faceplate to an exterior portion of an opposite faceplate, and means for reducing a stress concentration of an attachment load from an exterior portion of one faceplate.
After the assembly module is filled to an acceptable level, and a desired post-tensioning is completed, the method may proceed with S1700 where the method is complete.
Further structural details regarding an exemplary assembly module are discussed with reference
Configurations such as those depicted in
In alternative embodiments, a first faceplate, similar to faceplate 212, may be provided and portions of through connector assemblies secured to the first faceplate prior to positioning a second plate, such as faceplate 210. A subset of the through connector assemblies may be used to accurately position the second faceplate.
Additionally, as discussed further below, through holes such as 220, 222 may be threaded in order to allow positive engagement of a sleeve, rod, bolt, or the like, with the faceplate.
As discussed above, an assembly module, such as depicted in
As shown in
In embodiments, a width W of the wall assembly may be greater than 29 inches. Such thicknesses may be useful in specialized construction applications, such as walls of nuclear facilities that require radiation shielding as well as significant structural strength. In embodiments, an intermediate plate 340 may also be provided in the wall assembly 300. Intermediate plates may also be useful in providing improved fire resistance, and improved resistance to blast, missiles and the like. For transportation purposes, the L of an individual module may be approximately 60 feet or less to allow a module to be transported on a standard flatbed truck. Likewise, an exemplary H for a module may be approximately 12 feet or less. Of course, modules of greater size than the exemplary dimensions provided are also possible within the scope of the invention. Additionally, instead of placing assembly modules individually, a plurality of assembly modules may be joined together at a construction site and moved together, such as by crane, to a desired placement.
Aspects of an exemplary connector assembly including a securing mechanism are depicted in
Aspects of an additional exemplary connector assembly including a securing mechanism are depicted in
A base plate 540 may be secured via washer 560 and bolt 530. Thus, external forces applied to a connector such as base plate 540 may be transmitted via bolt 530 to a through connector assembly including sleeve 510.
Aspects of an additional exemplary connector assembly including a securing mechanism are depicted in
Aspects of an additional exemplary connector assembly including a securing mechanism are depicted in
Aspects of an additional exemplary connector assembly including a securing mechanism are depicted in
Aspects of an additional exemplary connector assembly including a securing mechanism are depicted in
Aspects of an additional exemplary connector assembly including a securing mechanism are depicted in
Such a configuration is usable, for example, in an assembly module as depicted in
As indicated previously, individual through connector assemblies may be attached with an intermediate plate without passing through the full distance of a transverse void. For example, as depicted in
The invention has been described with reference to exemplary embodiments. Modifications and alterations of the described embodiments may be evident to those of ordinary skill in the art upon a reading and understanding of the specification. The present invention is intended to include also such modifications and alterations in so far as they come within the scope of the appended claims, or the equivalents thereof.
Claims
1. An assembly module for a composite wall, the assembly module comprising:
- opposing faceplates with a transverse void between said faceplates;
- a plurality of through connector assemblies at least partially spanning the transverse void and connected with at least one of the opposing faceplates, said through connector assemblies including a securing mechanism that is configured to attach a portion of the connector assembly in the transverse void with the at least one faceplate from an outside of the at least one faceplate.
2. The assembly module of claim 1, further comprising at least one intermediate plate positioned between said opposing faceplates and connected with at least one of said through connector assemblies.
3. The assembly module of claim 1, wherein said securing mechanism is mechanical.
4. The assembly module of claim 1, wherein:
- a threaded portion of the connector assembly protrudes through holes in each of the opposing faceplates; and
- said securing mechanism includes a nut configured to be attached to the threaded portion of the connector assembly.
5. The assembly module of claim 4, said securing mechanism further comprising a second nut configured to be attached to the threaded portion of the through connector.
6. The assembly module of claim 1, wherein:
- a male threaded portion of at least one of the connector assemblies is engaged with a female threaded portion of a hole in at least one of the faceplates.
7. The assembly module of claim 1, wherein at least one of the through connector assemblies comprises a sleeve between the opposing face plates.
8. The assembly module of claim 7, wherein said sleeve defines a distance between the opposing faceplates.
9. The assembly module of claim 7, wherein said sleeve defines a distance between one of the faceplates and an intermediate plate.
10. The assembly module of claim 1, wherein:
- at least one of the through connector assemblies penetrates at least one of the faceplates; and
- the at least one through connector assembly includes a stopping mechanism at an end of the through connector assembly that positions the connector assembly with respect the at least one faceplate.
11. The assembly module of claim 10, wherein said stopping mechanism includes a nut attached to a threaded portion of the through connector assembly.
12. The assembly module of claim 1, wherein:
- at least one of the through connector assemblies includes a sleeve with a female threaded portion;
- at least one of the opposing faceplates includes a hole substantially where the at least one through connector assembly connects with the at least one faceplate; and
- the securing mechanism includes a bolt configured to be inserted through the hole in the at least one faceplate and engaged with the female threaded portion of the sleeve.
13. The assembly module of claim 1, wherein the through connector assemblies include at least partially threaded rods that traverse the transverse void.
14. The assembly module of claim 1, wherein the through connector assemblies include at least partially threaded sleeves that traverse the transverse void.
15. The assembly module of claim 1, wherein the securing mechanism is adjustable from an outside of the assembly module after the securing mechanism is secured.
16. The assembly module of claim 1, wherein the faceplates comprise sheets of material including through holes, and said securing mechanism is configured to attach with said through connectors through said through holes.
17. The assembly module of claim 1, wherein said through connectors are mechanically attached with the faceplates substantially without welding of said through connectors to the faceplates.
18. The assembly module of claim 1, wherein the transverse void has a width greater than 29 inches.
19. The assembly module of claim 1, further comprising a concrete fill material that substantially fills the transverse void,
- wherein, said faceplates consist essentially of steel plate material.
20. An assembly module for composite wall comprising:
- opposing faceplates with a transverse void between said faceplates;
- means for connecting said faceplates across the transverse void; and
- means for adjusting a tension of said means for connecting after the transverse void is filled with a fill material.
21. The assembly of claim 20, further comprising:
- means for adjusting a tension of said means for connecting before the transverse void is filled with the fill material.
22. The assembly of claim 20, further comprising:
- means for transmitting an attachment load from an exterior portion of one faceplate to an exterior portion of an opposite faceplate.
23. The assembly of claim 20, further comprising:
- means for reducing a stress concentration of an attachment load from an exterior portion of one faceplate.
24. A method of constructing a composite wall comprising:
- providing opposing faceplates;
- attaching the opposing faceplates with a plurality of through connector assemblies that span a transverse void between the faceplates including applying a connecting mechanism from an outside of at least one of the faceplates to attach with portions of the through connector assemblies in the transverse void; and
- filling the transverse void with a fill material after attaching the opposing faceplates with the plurality of through connector assemblies.
25. The method of claim 24, wherein the connecting mechanisms is adjustably connected with the through connectors.
26. The method of claim 24, further comprising:
- after filling at least a portion of the transverse void with the fill material, adjusting the connecting mechanism such that a tension of at least one of the through connectors is changed.
27. The method of claim 24, further comprising:
- before filling the transverse void with the fill material, adjusting the connecting mechanism such that a tension of at least one of the through connectors is set to a desired tension.
28. The method of claim 24, further comprising:
- attaching an external connector with at least one of the through connectors via the connecting mechanism.
29. The method of claim 24, wherein attaching the opposing faceplates with a plurality of through connector assemblies includes:
- placing a plurality of sleeves between the opposing faceplates;
- for each of the plurality of sleeves, inserting a rod through a hole in one of the opposing faceplates, through the respective sleeve, and out of a hole in the other of the opposing faceplates; and
- securing the rods from an outside of at least one of the opposing faceplates.
30. The method of claim 24, wherein attaching the opposing faceplates with a plurality of through connector assemblies includes engaging a male threaded portion of at least one of the connector assemblies with a female threaded portion of a hole in at least one of the faceplates.
31. A method of constructing a composite wall in a building comprising:
- providing a pre-assembled wall assembly module including at least two opposing faceplates, and a plurality of through connector assemblies attached with said faceplates;
- placing the pre-assembled wall assembly module in a position that the wall assembly module will occupy in the building;
- after the pre-assembled wall assembly module occupies the position, filling a transverse void between said faceplates with a fill material;
- adjusting a tension of at least one of said through connector assemblies after the transverse void is filled with the fill material at least to a height of the at least one through connector assembly.
32. The method of claim 31, wherein said adjusting the tension of the at least one through connector assembly includes adjusting a threaded portion of a connecting device engaged with a sleeve of the at least one through connector assembly.
33. The method of claim 31, further comprising:
- attaching an external connector with at least one of the through connectors via a connecting mechanism on one side of the composite wall; and
- attaching the external connector with at least one load distributing device on an opposite exterior side of the composite wall via the at least one through connector.
Type: Application
Filed: Nov 14, 2009
Publication Date: May 19, 2011
Applicant: Bechtel Power Corporation (Frederick, MD)
Inventor: Sanjeev Malushte (Bethesda, MD)
Application Number: 12/618,706
International Classification: E04G 9/00 (20060101); E04B 1/00 (20060101);