Patent Publication Number: US-2004040224-A1

Title: Mounting of tubular steel columns on concrete base

Description:
FIELD OF THE INVENTION  
       [0001] This invention relates general of the erection of tubular steel structures and is particularly directed to the mounting of a tubular steel column on a concrete base or footing.  
       BACKGROUND OF THE INVENTION  
       [0002] The construction of a steel structure incorporating tubular steel members typically involves securing a lower end of a tubular steel column to a support member such as a concrete footing, floor or foundation. A bolt, or bolts, disposed within the concrete support member are typically connected to a lower end of the tubular steel column by nuts in a conventional manner. One or more bolts are typically connected to an outer portion of the lower end of the tubular steel column, or a single bolt is inserted through an aperture in the column&#39;s base plate and secured thereto by means of a nut. The former approach leaves the mounting bolts visible after construction of the structure and is thus aesthetically undesirable, and also presents a tripping hazard to those in the vicinity of the tubular steel column. The latter approach involving a single bolt inserted through the column&#39;s base plate does not provide stable column mounting during erection of the structure and has resulted in construction accidents frequently involving injuries to workers.  
       [0003] The present invention addresses the aforementioned problems encountered in the past by providing for the safe and secure mounting of a tubular steel column on a concrete support base employing plural anchor bolts inserted through spaced apertures in the column&#39;s base plate. The nut and bolt combinations are precisely arranged in predetermined patterns, are hidden from view and do not present a safety risk.  
       OBJECTS AND SUMMARY OF THE INVENTION  
       [0004] Accordingly, it is an object of the present invention to provide for the stable, secure mounting of a tubular steel column on a support base such as a concrete footing.  
       [0005] It is another object of the present invention to attach a tubular steel column to a support base using plural anchor bolts extending from the support base and disposed within the column for increased safety and improved aesthetics.  
       [0006] A further object of the present invention is to provide an arrangement for mounting a tubular steel beam on a concrete footing wherein the mounting hardware and electrical access for running wires such as for lighting is disposed entirely within the column and hidden from view.  
       [0007] Yet another object of the present invention is to provide for the positioning of plural mounting bolts in a support base such as a concrete footing for attachment to a tubular support column, where the bolts are precisely arranged in a predetermined, spaced pattern for insertion through apertures in the column&#39;s base plate and are disposed within the column and thus hidden from view.  
       [0008] The present invention contemplates an arrangement for mounting a tubular steel column on a concrete base with the tubular steel column having upper and lower ends and a lateral wall portion disposed therebetween. The inventive mounting arrangement comprises a base plate attached to a lower end of the tubular steel column and including plural spaced first apertures disposed within the lateral wall portion of the tubular steel column; plural nut and bolt combinations attached to the concrete base, wherein the bolts are arranged in a predetermined pattern in the concrete base and each bolt is inserted through a respective first aperture for mounting the tubular steel column to the concrete base; and a second aperture in the tubular steel column providing access to the nut and bolt combinations within the tubular steel column for securing the nut and bolt combinations to the base plate. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009] The appended claims set forth those novel features which characterize the invention. However, the invention itself, as well as further objects and advantages thereof, will best be understood by reference to the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawings, where like reference characters identify like elements throughout the various figures, in which:  
     [0010]FIG. 1 is a partially cutaway side elevation view of a tubular steel column mounted to a concrete base in accordance with the principles of the present invention;  
     [0011]FIG. 2 is an upper perspective view illustrating a tubular steel support frame positioned upon and mounted to concrete casings, or footings, in accordance with the present invention;  
     [0012]FIG. 3 is a perspective view shown partially in phantom of an arrangement for mounting a tubular steel column on a concrete base in accordance with the present invention;  
     [0013]FIG. 4 is a top plan view of a portion of the tubular steel column mounting arrangement of the present invention illustrating the orientation and positioning of each of the column&#39;s base plates in a structure which includes four tubular steel columns;  
     [0014]FIG. 5 is a perspective view of a combination of plural mounting bolts and an anchor bolt template used for proper positioning of the anchor bolts in the concrete support base in accordance with another aspect of the present invention; and  
     [0015]FIGS. 6 and 7 are sectional views of the tubular steel column mounting arrangement of the present invention respectively showing the mounting bolts disposed in a square and a diamond configuration in the column&#39;s mounting plate. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0016] Referring to FIGS. 1 and 3, these are respectively shown a partially cutaway side elevation view and a perspective view shown partially in phantom of a tubular steel mounting arrangement  10  in accordance with the principles of the present invention. The tubular steel columns used with the present invention are typically incorporated in a steel frame building  30  as shown in the perspective view of FIG. 2, where each column is disposed in a respective corner of the steel frame building as shown in FIG. 4. However, the tubular steel columns with which the present invention is intended for use may be located virtually anywhere within the building.  
     [0017] As shown in FIG. 2, the steel frame building  30  includes four generally vertical tubular steel columns  12 ,  32   a ,  32   b  and  32   c . Each of the tubular steel columns  12 ,  32   a ,  32   b  and  32   c  is connected at its upper end to one or more structural members such as an eave or ridge beam, or a truss which form an upper portion of the steel frame building  30 . The lower end of each of the tubular steel columns  12 ,  32   a ,  32   b  and  32   c  is positioned upon, supported by and connected to a respective concrete footing  14 ,  34   a ,  34   b  and  34   c  in accordance with the present invention. As shown in FIG. 4, each of the four tubular steel columns  12 ,  32   a ,  32   b  and  32   c  is disposed in a respective corner of the steel frame building.  
     [0018] Details of the manner in which each tubular steel column is connected to a respective concrete footing by means of the tubular steel column mounting arrangement  10  of the present invention will now be described with reference to FIGS. 1 and 3. The tubular steel column mounting arrangement  10  securely connects a tubular column  12  to a support base, such as a concrete footing, or foundation,  14 . The tubular steel column  12  includes a hollow, upper tubular member  16  having a metal base plate  18  attached to its lower end by weldments  26  as shown in FIG. 1. Disposed in a spaced manner in the column&#39;s base plate  18  are plural apertures each adapted to receive a respective anchor bolt for securely attaching the base plate to the concrete footing. Thus, in the embodiment shown in FIGS. 1 and 3, each of four apertures in the column&#39;s base plate  18  is adapted to receive a respective one of four anchor bolts  22   a ,  22   b ,  22   c  and  22   d . Each of the anchor bolts  22   a - 22   d  is positioned within the concrete footing  14  as it sets so as to be securely and fixedly attached to the concrete footing after it cures and hardens. Each of the four anchor bolts  22   a - 22   d  has on its upper end a respective threaded portion for receiving a nut thereon as shown in the figures. Thus, the upper ends of anchor bolts  22   a ,  22   b ,  22   c  and  22   d  are respectively adapted to receive and securely engage coupling nuts  24   a ,  24   b ,  24   c  and  24   d . By tightening each of the coupling nuts  24   a - 24   d  on a respectively one of the anchor bolts  22   a - 22   d , the column&#39;s base plate  18 , and thus the column itself, may be securely and fixedly mounted to the concrete footing  14 .  
     [0019] A lateral portion, i.e., sidewall, of the lower end of the tubular steel column  12  includes an access aperture, or opening,  20 . It is by means of the access aperture  20  that each of the nuts  24   a ,  24   b ,  24   c  and  24   d  may be positioned on a respective upper threaded portion of one of the anchor bolts and tightened. The access aperture  20  is sized so as to be able to accommodate a wrench or other nut tightening device for securely connecting the lower end of the tubular steel column  12  to the concrete footing  14 . A removable cover plate  28  is adapted for attachment to the lateral portion of the tubular steel column  12  so as to cover the access aperture  20 . Cover plate  28  is positioned on the tubular steel column  12  over the access aperture  20  therein after the nuts are tightening on each of the respective anchor bolts. Cover plate  28  may be removably maintained in position over the access aperture  20  by any of various means such as positioning screws  36  shown in FIG. 1 or by a mounting flange  52  (shown in dotted line form) which is adapted to receive the cover plate  28  in a sliding manner and maintain the cover plate in position over the access aperture  20 . The tubular steel column&#39;s base plate  18  includes an electrical access aperture  27  to permit electrical leads (not shown) to extend upward from the concrete footing  14  into the tubular steel column so as to be hidden from view. This electrical wiring may be used to provide lighting, grounding, signs, etc., in the building structure.  
     [0020] Referring to FIG. 5, there is shown a perspective view of an anchor bolt template  40  for precisely positioning four anchor bolts  42   a ,  42   b ,  42   c  and  42   d  within a concrete footing in accordance with another aspect of the present invention. The concrete footing is not shown in FIG. 5 for simplicity, it being understood that the anchor bolt template  40  is positioned on the upper surface of the concrete footing after the four anchor bolts  42   a - 42   d  are inserted into the concrete footing shortly after it is poured and while the concrete footing is curing. The anchor bolt template  40 , which also is preferably comprised of a high strength steel, includes plural spaced apertures each adapted to receive a respective anchor bolt. Anchor bolt template  40  further includes a centering aperture  46  and an electrical access aperture  48 . Centering aperture  46  is used for precise positioning of the anchor bolt template  40  as well as the four anchor bolts in the concrete footing, such as shown in FIG. 4, where the center of each of the tubular steel columns  12 ,  32   a ,  32   b  and  32   c  is located precisely at the corner of the square building structure  38  which is shown in the figure in dotted line form. The electrical access aperture  48  permits electrical wiring such as for lightening, grounding, signs, etc., to be positioned within the tubular steel column and thus be hidden from view. Finally, the anchor bolt template  40  includes a center reference indicator  50  which points to the center of the structure being constructed and which insures proper positioning and orientation of the anchor bolt template and thus the tubular steel column within the structure being constructed.  
     [0021] Referring to FIG. 6 there is shown a sectional view of a tubular steel column  58  having a base plate  60  and an access aperture  62 . Disposed within the tubular steel column  58  and inserted through respective apertures in the column&#39;s base plate  60  are first, second, third and fourth nut/bolt combinations  64   a ,  64   b ,  64   c  and  64   d . The nut and bolt combinations  64   a - 64   d  in FIG. 6 are arranged in a generally rectangular, or more particularly a square, array by the anchor bolt template previously described. Similarly, shown in FIG. 7 is a sectional view of a tubular steel mounting arrangement including a tubular steel column  68 , having a column base plate  70  and an access aperture  72 . Disposed within the tubular steel column  68  and inserted through a respective aperture in the column&#39;s base plate  70  are first, second, third and fourth nut/bolt combinations  74   a ,  74   b ,  74   c  and  74   d . The four nut and bolt combinations  74   a - 74   d  shown in FIG. 7 are arranged in a diamond-shape also by means of the above described anchor bolt template. The anchor bolt template may be used to precisely position and align virtually any number of anchor bolts in virtually any geometric array for precise mounting and alignment of the nut/bolt combinations within a tubular steel column in accordance with this aspect of the invention.  
     [0022] While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the relevant arts that changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.