JOIST ASSEMBLY WITH SHAPED CHORD CHANNEL

BACKGROUND OF THE INVENTION

CITATION TO PRIOR APPLICATIONS

[0001]The present application claims priority to U.S. Provisional Application No. 63/743,983, titled "Shaped Joist Chord" and filed on January 10, 2025, which is, along with all references therein, entirely incorporated by reference herein. The present application also claims priority to U.S. Provisional Application No. 63/784,667, titled "Shaped Joist Chord" and filed on April 7, 2025, which is, along with all references therein, entirely incorporated by reference herein.

BACKGROUND AND INVENTION SUMMARY

[0002] Joists remain a key element to construction projects by providing an effective method to distribute loads across wide spaces. Conventional joist assemblies include open web steel joists often used in larger facilities. These open web steel joists generally use back-to-back structural angles for chord members that make up the top and bottom chords of a joist. As shown in FIG. 1, such conventional systems feature an open channel or groove into which web members may be disposed and ultimately attached to the chord members.

[0003] This conventional design, however, requires precise welding (or other attachment) of each web member between the chord members as shown in FIG. 9. This precision is time consuming and labor intensive. At present, there is no known method to safely expedite the assembly of joists according to this conventional design.

[0004] An object of the present disclosure is to provide an improved joist assembly configuration that both maintains the safety and load-distribution of earlier designs but also reduces the complexity of installation. The present disclosure further contemplates that installation of joist assemblies as disclosed herein may be at least partially automated.

[0005] Other aspects, embodiments, and features of the present disclosure will become apparent from the following Detailed Description when considered in conjunction with the accompanying Figures.

BRIEF DESCRIPTION OF DRAWINGS

[0006] The preceding aspects and many of the attendant advantages of the present disclosure will become more readily appreciated by reference to the following figures and description of various exemplary embodiments. The drawings briefly described below are presented for ease of explanation and do not limit the scope of any claimed subject matter.

[0007]FIG. 1 is a front view of a prior art joist.

[0008]FIG. 2 is a front view of a joist assembly chord member in accordance with embodiments of the present disclosure.

[0009]FIG. 3A is a side view of a joist assembly in accordance with embodiments of the present disclosure.

[0010]FIG. 3B is a front view of a joist assembly in accordance with embodiments of the present disclosure.

[0011]FIG. 4 is a front view of a joist assembly chord member in accordance with embodiments of the present disclosure.

[0012]FIG. 5 is a front view of a joist assembly chord member in accordance with embodiments of the present disclosure. FIG. 6 is a side view of a joist assembly in accordance with embodiments of the present disclosure.

[0013]FIG. 7 is a side view of a joist assembly in accordance with embodiments of the present disclosure.

[0014]FIG. 8 is a partial side view of a joist assembly in accordance with embodiments of the present disclosure.

[0015]FIG. 9 is a bottom perspective view of a prior art joist. FIG. 10A is a rotated partial front view of a chord and web member of a joist assembly in accordance with embodiments of the present disclosure. FIG. 10B is a perspective view of a web member in accordance with embodiments of the present disclosure.

[0016]FIG. 11A is a rotated front view of a web member in accordance with embodiments of the present disclosure.

[0017]FIG. 11B is a perspective view of a web member in accordance with embodiments of the present disclosure.

[0018]FIG. 11C is a rotated partial front view of a chord and web member of a joist assembly in accordance with embodiments of the present disclosure. FIG. 11D is a rotated partial front view of a chord and web member of a joist assembly in accordance with embodiments of the present disclosure. FIG. 12 is a perspective view of a web member in accordance with embodiments of the present disclosure.

[0019]FIG. 13 is a perspective view of a web member and pipe clamp in accordance with embodiments of the present disclosure.

[0020]FIG. 14 is a front view of a bottom chord member with a threaded rod in accordance with embodiments of the present disclosure.

[0021]FIG. 15A is a rotated front view of a web member in accordance with embodiments of the present disclosure.

[0022]FIG. 15B is a rotated front view of a web member in accordance with embodiments of the present disclosure.

[0023]FIG. 16A is a top view of a web member before rolling in accordance with embodiments of the present disclosure

[0024]FIG. 16B is a top view of a web member before rolling in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

[0025]An exemplary embodiment of a joist assembly 1 in accordance with the present disclosure is depicted in FIG. 3A with individual, constituent components are shown in FIGS. 3B and 10A-11D. Joist assembly 1 may include a top chord member 100, a bottom chord member 200, and one or more web members 300 attached to an outward-oriented surface of a chord member.

[0026]Both top chord member 100 and bottom chord member 200 share similar structural features. Each chord member may comprise one or more vertical sides 101/201 and a horizontal channel base 102/202 which partially define a channel 103/203. Additionally, the chord members may comprise one or more horizontal legs 104/204 and one or more lips 105/205 extending from such legs. For purposes of this description, the various elements may be referred to with respect to either a top or bottom chord member, but this disclosure contemplates that such description could be applied to the other chord member or both chord members simultaneously.

[0027]In certain embodiments, as shown in FIG. 2, top chord member 100 may be roll formed to have a hat-shaped channel 103 at least partially defined by vertical sides 101 and horizontal channel base 102. The chord members may be formed from steel. The thickness of steel in hat-shaped channel 103 may be between 0.1"-0.375". In further embodiments, each horizontal leg 104 may be between 1.5"-4". Vertical sides 101 may be between 2"-6" in height. Horizontal channel base 102 may be between 1"-2". Lips 105 may be between 3/8"-1". The radius of any bends may range between 0.19-0.7. The hat-shaped channel is stronger than conventional double angle chord designs. Lips 105 provide increased structural strength. Additionally, when deck installed, joint assembly 1 provides box beams while eliminating the need for joist seats as the chord members sit flush. Moreover, bottom chord 200 may be braced off the top or bottom of the chord member.

[0028]The joist assembly can be formed by orienting top chord member 100 such that hat- shaped channel 103 is facing substantially downward while bottom chord member 200 is oriented such that hat-shaped channel 203 is facing substantially upward opposite top chord member 100. One or more web members 300 may be disposed between top chord member 100 and bottom chord member 200. In some embodiments, web members 300 may be U-shaped member structures, be angled with crimped ends, or be otherwise capable of forming a lattice in conjunction with top chord member 100 and bottom chord member 200.

[0029]In further embodiments, the chord members may comprise at least one stiffening rib 106/206, as shown in FIG. 4, to increase the strength of the respective chord. The addition of such a rib increases the moment of inertia or bending resistance thus reducing stress and deflection. The stiffening rubs may be incorporated into the horizontal channel base or horizontal legs.

[0030] In alternative embodiments, the hat-shaped channels of the chord members may be substantially dovetail shaped as depicted in FIG. 5. This channel design features angled vertical sides that increase strength over the channel.

[0031]Additionally, in even further embodiments, one or more apertures 107/207 may be formed or punched into the horizontal channel base of the chord members to provide a layout or markings for the position of web members to be installed. This simplifies fabrication as conventional approaches utilize manual layout and each web member. FIG. 6 depicts a joist assembly having guiding apertures. Conventional equipment may be configured to punch pre- determined apertures based on integration with joist design software. Each aperture would correspond to web member size plus some allowable tolerance. The apertures may be punched into the chord material during the roll forming described above by a hydraulic or other conventional system capable of making the apertures.

[0032] The stable hat shape also allows for enhanced automation or other simplification of fabrication/installation. Robotic welding systems may be utilized along both chord members to spot weld web members thereto forming an open web steel joist. The use or arc spot welding allows for greater tolerance on the location of the weld and for welding to be done from outside the chord members as opposed to inside as in conventional approaches shown in FIG. 9. As such, robotic welding may be used in creating the joist assembly. FIGS. 7 and 8 illustrate exemplary positions for spot welding to occur along the joist assembly. In some embodiments, the arc spot welds may be made along the center line of a web member and be 5/8" or 3/4". This is unlike conventional joist approaches in which web member engagement is very labor intensive and cannot be achieved through robotic welding.

[0033]Web members 300 may also be configured to provide improved functionality in the disclose joist assemblies. As shown in FIGS. 10A and 10B, in some embodiments, a web member 300 may comprise at least one side 301, a base 302, and a channel 303 at least partially defined by side 301 and base 302. Each web member 300 may be positioned such that a side (or two sides) 301 are layered on top of corresponding chord vertical side(s) 101 (or 201). The web member and chord member may then be engaged with arc spot welding at the position in which side 301 and vertical side(s) 101 (or 102) overlap. The length of a web member may vary depending on the desired joist depth. The width of a web member may be substantially that of the chord member's channel with a tolerance of approximately 1/16".

[0034]Exemplary web members in accordance with various embodiments of the present disclosure are depicted in FIGS. 15A-16B. As shown, a web member 300 may optionally include return legs 307. Such return legs provide increased bending resistance and strength. The dimensions of a web member may vary. In FIGS. 15A and 15B, the exemplary web members have a base 302 width of 1.5" with a contemplated range of between 1"-3". In practice, the width here will be determined by the width of the chord(s) to which the web member will attach. The vertical sides 301 are 1.5" with a contemplated range of between 1"-3". Optional return legs 307 are shown as being 1/2" with a contemplated range of between 1/4"-1". The radius of bends in the depicted exemplary web members may range from 0.1-0.5.'

[0035]In other embodiments, web member 300 may further comprise one or more notches 304 formed into one or both ends of the web member as shown in FIGS. 11A-D. Notched web members in accordance with these embodiments may be substantially U-shaped and have sides 301 that are greater in length than base 302. One or more notches 304 may result in one or more sides 301 extending beyond base 302 on either or both ends of web member 300 effectively creating "tabs." Such extended section(s) may be positioned such that they are layered on top of corresponding chord vertical side(s) 101 (or 201). The web member and chord member may then be engaged with arc spot welding at the position in which the extended section(s) of the web member and vertical side(s) 101 or 102 overlap. The notches allow for generally improved welding efficiency while also allowing for robotic welding.

[0036]Similar to the chord members, a web member in accordance with various embodiments of this disclosure may composed of steel having a thickness in channel 303 of between 0.1"-0.375". A web member may likewise be roll formed. As shown in FIGS. 16A and 16B, for web members having a notch 304, the base material may have the notch made (be it punched, cut, or otherwise removed out of the base material) prior to roll forming. Moreover, for those web members having return legs 307 for increased strength in the structural member, the base material may be further rolled to form those legs opposite base 302.

[0037] In further embodiments, each web member 300 may be configured to facilitate attachment of conduit and other mechanical, electrical, or plumbing connections to the joist

[0038]assembly. For example, seen in FIG. 12, a strut channel web may be utilized having one or more web apertures 305 formed into base 302. FIG. 13 depicts another embodiment in which a pipe clamp may be disposed within channel 303. The joist assembly mayfurther have a "Unistrut style" bottom chord attachment as seen in FIG. 14. The use of a threaded rod 1401, corresponding nuts 1402, and washers 1403 provides bottom chord attachment at the center of the chord member resulting in no moment load being applied. This contrasts to conventional web members which are often crimped angle, round bar, or some other structure that similarly impedes attachment of other elements while also requiring manually intensive labor to attach to chord members.

[0039] The section headings herein are provided for consistency with the suggestions under 37 C.F.R. § 1.77 or to provide organizational cues. These headings shall not limit or characterize the invention(s) set out in any claims that may issue from this disclosure. Further, a description of a technology as background information is not to be construed as an admission that particular technology is prior art to any embodiment(s) in this disclosure. Neither is the "Summary" a characterization of the embodiment(s) outlined in issued claims.

[0040] Furthermore, any reference in this disclosure to "invention" or "embodiment" in the singular should not be used to argue that there is only a single point of novelty in this disclosure. Multiple embodiments may be set forth according to the limitations of the multiple claims issuing from this disclosure. Such claims accordingly define the embodiment(s) and their equivalents that are protected thereby. In all instances, the scope of such claims shall be considered on their own merits in light of this disclosure but should not be constrained by the headings set forth herein.

[0041] Moreover, the Abstract is provided to comply with 37 C.F.R. § 1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the preceding Detailed Description, it can be seen that various features may be grouped in a single embodiment to streamline the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Instead, as the

[0042]claims reflect, the inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.