Abstract:
Apparatus are provided for a curtain wall anchor system. The curtain wall anchor assembly may include various anchor configurations. Each anchor embodiment is intended to reduce labor time and costs and eliminate extraneous steps in the construction process involving curtain walls. Each possible anchor assembly also features an optional component of attaching a concrete anchor for optimizing load paths and solving issues of bending in traditional edge angle pour stops.

Description:
TECHNICAL FIELD 
     The present disclosure relates to an apparatus and system for providing for some adjustability for installation of curtain walls and for transferring the loads associated with the curtain walls to structural elements of the buildings. The present disclosure eliminates industry problems associated with wavy edge of slab pour stops constructed of bent plates and reduces considerably or eliminates the significant coordination between the construction trades thereby reducing installation costs. 
     BACKGROUND 
     Curtain walls are the outer covering of a building in which the outer walls are non-structural, and merely keep the weather out and occupants of the building in the building. A curtain wall does not carry any dead load weight from the building other than its own dead load. In this context a dead load, or also commonly referred to as a static load, includes loads that are relatively constant over time, including the weight of the structure itself, and immovable features such as walls, plasterboard or carpet. Curtain walls are designed to resist air and water infiltration, sway induced by wind and seismic forces acting on the building and its own static load weight forces. Exterior wind loads combined with the curtain wall&#39;s own weight are transferred to the building through, for example, anchors at specific points of attachment. Curtain walls may be attached to anchors via different methods. Typical curtain wall assemblies include structural members called mullions which separate and secure the curtain wall panels. The mullions are secured to the building via curtain wall anchors. Curtain wall anchors are the connection means between the curtain wall mullions, to the building structure. 
     Typical building construction techniques with steel supported concrete floor slabs employ a bent steel plate fixed to spandrel beams as pour stops for concrete. The bent plate pour stops may also be referred to as edge angles. Considerable time is required at a steel fabricator to bend all of the plate to install as pour stops. The bent plate pour stops are then taken to the job site, positioned, and welded on top of the spandrel beams. Bent plates often provide a wavy edge of the slab with significant deviation of the actual edge from planed location. The deviation creates difficulties in attachment of a curtain wall while trying to maintain a controlled planar surface in the outer surface of the curtain wall. Additionally, the curtain wall is typically attached to the bent plate pour stop via clip angles welded to the pour stop or supporting beam. This requires considerable time and labor to position the curtain wall anchors and weld them in place. The welding also requires costly skilled laborers and adds significantly to the overall construction schedule. 
     Occasionally embedded anchor channels are specified for a building slab edge to allow for curtain wall attachment. These typically require cutting the steel pour stop and welding sections of anchor channels or block-outs for top mounted anchor channels in the concrete slab. Although these options allow for some adjustability for the curtain wall installation they still do not account for the wavy bent plate slab edge and they require significant coordination between construction trades in addition to being costly to install. 
     One of the concerns in using existing anchor channels welded to steel edge angles is that excessive loads can cause the edge angle to bend. Structural engineers are regularly confronted with this issue and by contractors who want easier/faster construction techniques. The disclosed curtain wall anchor system embodiments include options for providing a direct or indirect load path into the concrete slab or steel beam to prevent edge angle bending and provide faster, less costly construction. 
     SUMMARY 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key factors or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     In various embodiments, methods and systems for curtain wall anchors are provided. In particular, various curtain wall anchor systems are described herein to streamline the process of placing curtain walls and to reduce labor time and cost associated with installation of curtain walls. 
     In a first embodiment, an anchor assembly is provided. The anchor assembly comprises an outwardly extending horizontal flange member configured for engagement with at least a portion of a building support member, such as an I-beam, and an anchor channel configured for engagement with at least a portion of a curtain wall assembly, wherein the anchor channel is disposed opposite the horizontal flange member. 
     A second embodiment of an anchor assembly comprises an outwardly extending horizontally oriented flange configured for engagement with at least a portion of a building support member such as an I-beam; a first vertically extending flange configured for engagement with at least a portion of a curtain wall assembly; and a second vertically extending flange for engagement with a reinforcing member encased in the concrete slab wherein the first and second vertically oriented flanges are separated by a gap. 
     In yet another embodiment, a method of installing a curtain wall anchor assembly is provided. The claim recites, providing a curtain wall anchor assembly, wherein the curtain wall anchor assembly includes a pour stop anchor comprising: an anchor channel extending a length of the pour stop anchor, wherein the anchor channel is configured for engagement with at least a portion of a curtain wall bracket; a posterior straight edge located on an opposite side of the anchor channel; and a posterior flange for engagement with at least a portion of a building structure; applying a concrete support slab subsequent to placement of the pour stop anchor assembly; and attaching a curtain wall attachment fitting to the anchor channel of the pour stop anchor assembly. 
     Further embodiments and aspects will become apparent by reference to the drawings and by study of the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Illustrative embodiments of the present invention are described in detail below with reference to the attached figures, which are incorporated by reference herein and wherein: 
         FIG. 1  depicts a perspective view of an embodiment of a curtain wall anchor system; 
         FIG. 2  depicts an elevation view of an embodiment of a curtain wall anchor system; 
         FIG. 3  depicts a plan view of an embodiment of a curtain wall anchor system; 
         FIG. 4  depicts a perspective view of an embodiment of a curtain wall anchor; and 
         FIG. 5  depicts an elevation view of an embodiment of a curtain wall anchor system. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, reference is made to the accompanying drawings, which form a part hereof and illustrate exemplary embodiments of the invention. In the drawings, reference numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the inventions, and it is to be understood that other embodiments may be utilized, and that structural, logical, and procedural changes may be made. 
     Various embodiments of a curtain wall anchor system are illustrated in  FIGS. 1-5 .  FIG. 1  depicts a curtain wall anchor system  100  and a pour stop  103 . Pour stops are used in the construction industry to provide a barrier when pouring concrete. The embodiment depicted in this figure is directed to a pour stop with an integral anchor extrusion. This configuration of a curtain wall anchor provides a means for anchoring a building curtain wall to a structural concrete floor slab and also forming an integral concrete pour stop. As illustrated, the curtain wall anchor system  100  may be positioned adjacent to, and preferably overlapping, a flange “F” of a structural steel support member  102 . The curtain wall anchor  100  is preferably welded to the flange F of the structural steel support member  102 . Once in place, the pour stop  103  of the curtain wall anchor system  100  provides a barrier to contain the spread of the poured concrete slab  101 . 
     As further depicted in  FIG. 1 , an anchor bolt  104  is used to secure a curtain wall bracket  105  to the anchor channel  111 . An additional bolt  106  may further secure the curtain wall bracket  105  to a curtain wall assembly  107 . Various types of anchor bolts  104  may be used. In a preferred embodiment, T-bolts are used. A T-bolt refers generally to a type of bolt having a crosspiece for a head or a bolt with a square head or rectangular shape intended to fit into the anchor channel  111  with the “T” part of the head rotated and securing the bolt in the channel.  FIG. 1  illustrates the use of the pour stop  103  with curtain wall installation. 
       FIG. 2  details an elevation view of the curtain wall anchor system  100  (illustrated in  FIG. 1 ) and details the utilization of reinforcing bar  177  embedded into the concrete slab  101 . The reinforcing bar extends to and is connected to the inside face  178  of the upper vertical flange  180 . The reinforcing bar  177  serves to develop loads into the concrete slab  101 . In practice a plurality of rebar will be embedded into the concrete slab for engagement with the upper vertical flange  180 .  FIG. 3  provides a plan view of the curtain wall bracket  105  to include a second curtain wall bracket  230  on the opposite side of the curtain wall assembly  107  secured to the pour stop  103 . 
       FIG. 4  details an alternative embodiment of a curtain wall anchor apparatus  400  and pour stop or upper vertical flange  200 . The anchor apparatus  400  is preferably constructed of steel to facilitate welding; however, other structurally rigid materials may be also be utilized with this disclosed technology. This embodiment of a curtain wall anchor includes a first aperture  109 , a slot  110 , a lower vertical flange  112 , an anchor channel  111 , an upper channel flange  113 , and a lower channel flange  114 . In application, the anchor apparatus  400  may be secured in place via welding to the structural steel support member  102 , as shown in  FIG. 5 . 
     As further depicted in  FIG. 4 , the anchor channel  111  is utilized to slidably secure a curtain wall bracket, as seen in  FIG. 5  at  105 , to the curtain wall assembly  107 . The anchor channel  111  is a void space forming a continuous slot along an outside edge of the anchor apparatus  400  to allow a keyed anchor block with a threaded bolt  115  to be attached thereto. As with the first embodiment, illustrated in  FIGS. 1 and 2 , the bolt  115  is slidably translatable within the anchor channel  111 . The anchor channel  111  includes an upper channel flange  113  and a lower channel flange  114  to limit the bolt  115  to slidable longitudinal translation. This ensures that the bolt  115  can slide within the anchor channel  111 , until tightened into position, but cannot be extracted perpendicular to the anchor channel  111 . 
     The anchor channel  111  is positioned between a larger upper vertical flange  200  and a descending flange  210 . The upper vertical flange  200  transitions to a web member  220  that connects the upper vertical flange  200  to the lower vertical wall member  112 . Additionally, the anchor assembly  400  may include a first aperture  109 . The first aperture  109  is preferably in the shape of a triangle. The aperture  109  of the optional triangular design reduces the amount of material used in the fabrication of the anchor  400  yet the triangular design utilizes strut members  109 A,  109 B, and  109 C to brace the loads on the extruded anchor  400 . 
       FIG. 5  details an elevation view of the curtain wall anchor system, shown in  FIG. 4 , with the pour stop  103  and first aperture  109 . Also illustrated in  FIG. 5  is the slot  110  and lower vertical wall member  112  that optionally is available to secure the pour stop  103 . In operation, the rebar  149  passes through a slot (not shown) in the upper edge of the lower vertical wall member  112 . A short section of the rebar  149  is then bent at a 90 degree angle and sits inside of the slot  110  running parallel to the lower vertical wall member  112 . When curtain wall loads are sufficiently high this short section of rebar  149 , when covered with concrete in the slab  101 , serves to provide additional load bearing capacity. Multiple rebar  149  rods will preferably be used along the length of the curtain wall anchor system and positioned with the curtain wall anchor apparatus  400  as noted immediately above. 
     It will be clear from the embodiments described above that the need for an edge angle has been eliminated due to the functionality of the pour stop  103 . Additionally, the pour stop provides for an adjustable anchor attachment since the anchor may be moved along the anchor channel  111  as desired. 
     In each of the embodiments of  FIGS. 1-5 , installation of the curtain wall will be quicker and less costly by eliminating positioning and welding of the curtain wall clip anchors to traditionally used edge angel pour stops. The designs make horizontal adjustment of curtain wall anchors quicker and simpler than with previous installation techniques. The disclosed designs also facilitate a uniform straight edge of the building slab edge for the installation of exterior walls. These designs thereby reduce the need for thicker steel edge angles required by structural designers for supporting eccentric curtain wall loads. Lastly, this design eliminates the need for studs or reinforcing welds to traditional edge angles to transfer eccentric loads from the curtain wall into the concrete slab. 
     In each of the described embodiments, where applicable, anchor channels may be customized to accommodate a variety of curtain wall attachment fittings and/or bolts. Additionally, each anchor assembly described herein may be made of steel or any other material that can sufficiently sustain the load associated with the particular situation. For example, a load for a construction project of a 15-story building will certainly differ from the load to withstand in a construction project of a 2-story building. 
     While the preferred form of the present invention has been shown and described above, it should be apparent to those skilled in the art that the subject invention is not limited by the figures and that the scope of the invention includes modifications, variations, and equivalents which fall within the scope of the attached claims. Moreover, it should be understood that the individual components of the invention include equivalent embodiments without departing from the spirit of this invention. 
     It will be understood by those of ordinary skill in the art that the order of the steps recited herein is not meant to limit the scope of the present invention in any way and, in fact, the steps may occur in a variety of different sequences within embodiments hereof. Any and all such variations, and any combinations thereof, are contemplated to be within the scope of embodiments of the present invention.