Abstract:
A method and apparatus for creating a reinforced vertical multi-sided monopole tower for supporting equipment including a multi-sided monopole, a plurality of holes on three equally spaced sides of the multi-sided monopole tower and tower reinforcement apparatus mounted to the holes. The tower reinforcement apparatus includes bolts supporting a first flat bar and a second flat bar on each side of the tower. The upper end of the first flat bar abuts a lower end of the second bar and a plate is bolted over adjacent ends connecting the first and second flat bar such that the first and second flat bars are sandwiched between the plate and a side of the perimeter of the monopole.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of and claims priority to U.S. application Ser. No. 11/159,689, filed on Jun. 23, 2005, which is a utility conversion of Provisional Application Ser. No. 60/582,160, filed on Jun. 24, 2004. The disclosures of U.S. application Ser. No. 11/159,689 and U.S. Provisional Patent Application No. 60/582,160 are incorporated herein by reference in their entirety. 
    
    
     STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This present invention relates to a means of increasing the load capacity of a monopole tower and in particular, an apparatus and method for increasing the load capacity and stability of the tower to support the weight of additional communication equipment as well as the environmental forces exerted on the tower. 
     2. Brief Description of Prior Art 
     Single-pole towers, also referred to as monopole towers are used in the telecommunications industry. In particular, such towers are used to support equipment for wireless phones and other communication devices. 
     The increase in wireless communications has resulted in an increase of mounted communication equipment of all kinds. Not only do wireless service providers need to install equipment covering new geographic areas, competing wireless service providers need to install additional equipment covering the same or similar geographic areas. The solution to the foregoing problem is to either purchase additional land to erect new towers, or install additional equipment on existing towers. Purchasing land to install additional towers is increasingly expensive, as well as the expense associated with the construction and the maintenance of a new tower. 
     Towers are designed generally to support the weight of the communications equipment originally installed on the tower, as well as to withstand forces exerted on the tower by environmental factors, such as wind and ice, for example. Towers are generally not designed with sufficient stability to enable the tower to allow for the installation of additional equipment. As a result, prior art methods of increasing the stability of the tower in order to support additional equipment are known to consist basically of familiar, expected and obvious structural configurations, typically reinforcing the weak area of the tower (the area where the additional equipment is to be installed) by means of a weld repair, such as an overlay of welding material. Installing the welding material can be done manually, or by using an automatic welding machine. 
     Therefore, it can be appreciated that there exists a continuing need for an apparatus and method for increasing the load capacity and stability of a tower to enable the tower to support the weight of additional communication equipment as well as the environmental forces exerted on the tower. 
     As will be seen from the subsequent description, the preferred embodiments of the present invention overcome limitations of monopole tower arrangements. 
     SUMMARY OF THE INVENTION 
     With the proliferation of cell phones and personal communications devices comes the need for towers to support additional equipment for wireless phone and other communication devices. The present invention is designed to increase the load capacity and stability of a tower to enable the tower to support the weight of additional communication equipment as well as the environmental forces exerted on the tower. The preferred embodiment generally includes vertical flat bars disposed about the tower and mounted to the tower with one-sided bolts. A joining plate is further disclosed when joining a first vertical flat bar with a second vertical flat bar. 
     The presence of the tower support elements of the present invention increases the load capacity and stability of the tower. Specifically, the vertical flat bars provide reinforcement to the tower to allow for the installation of additional equipment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a preferred embodiment of the present invention, a reinforced tower. 
         FIG. 1A  is a detail view of bolt spacing for an end of a vertical flat bar and joining plate. 
         FIG. 1B  is a detail view of a section of the apparatus of  FIG. 1 . 
         FIG. 1C  is a detail view of a full penetration weld between the vertical flat bar and the base flange. 
         FIG. 2  is a top view of the tower reinforcement apparatus of  FIG. 1 , illustrating the preferred spacing between the vertical flat bars. 
         FIG. 3  is a perspective view of the vertical flat bar and joining plate. 
         FIG. 3A  is a detail view of an end of the vertical flat bar and joining plate. 
         FIG. 4  is a perspective view of a monopole tower showing field drilled holes for receiving one-sided bolts. 
         FIG. 5  is a perspective view of a monopole tower showing installed one-sided bolts. 
         FIG. 6  is a cutaway detail view of the present invention showing one-sided bolts, the vertical flat bar, and the tower section. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIGS. 1-6  illustrate a preferred embodiment of a tower reinforcement apparatus  1  made in accordance with the present invention. In the preferred embodiment, the tower reinforcement apparatus  1  is attached to a prior art monopole tower  100  at selected locations to maximize the strength of the tower  100  and reinforce the tower  100  in order to enable the tower  100  to support the weight of additional communication equipment (not shown) as well as the environmental forces exerted on the tower  100 . 
     The prior art monopole tower  100  is generally attached to a base flange  110  and is comprised of a solid sheet of formed metal that forms a structure capable of supporting the various communication equipment that may be attached to the prior art tower  100 . 
     In general, the prior art monopole tower  100  is designed to support the weight of the communications equipment originally installed on the tower  100 , as well as to withstand forces exerted on the tower  100  by environmental factors, such as wind and ice, for example. The monopole towers of the prior art are generally not designed with sufficient stability to enable the tower  100  to allow for the installation of additional equipment. The tower reinforcement apparatus  1  is designed to attach to the prior art monopole tower  100  at selected locations where additional equipment will be installed in order to maximize the strength and provide reinforcement to the tower  100  at such selected locations. 
     In application, the tower  100  is drilled with a plurality of holes  105  at selected locations as shown in  FIG. 4  for receipt of one-sided bolts  150  preferably one-sided stitch bolts  150  as shown in  FIG. 5 . A vertical flat bar  10  having a plurality of apertures  11  attaches to the prior art monopole tower  100  with the plurality of one-sided stitch bolts  150  and nuts  150 A. The vertical flat bar  10  is attached to the tower  100  at selected locations in order to maximize the strength and provide reinforcement to the tower  100  at those selected locations. Further, the spacing of the bolts  150  along the vertical flat bar  10  can be considerably narrower to further increase the reinforcement. In the preferred embodiment, at least one one-sided termination bolt  155  and nut  155 A (shown in  FIG. 1B ) is installed at the approximate top end of the flat bar  10  to further secure the vertical flat bat  10  to the tower  100 . 
     As should be understood, the longer the vertical flat bar&#39;s  10  length, the more difficult the vertical flat bar  10  is to manage and handle when attaching the bar  10  to the tower  100  in the field. As such, when longer lengths of flat bar  10  is required, it is preferred to apply multiple vertical flat bars  10  to maximize the strength and provide reinforcement to the tower  100 . 
     As an example, and referring to  FIGS. 1 and 1B , a first vertical flat bar designated in  FIG. 1  as  10 A is attached at its upper end to the tower  100  as discussed above, and a second vertical flat bar designated as  10 B in  FIG. 1  is attached to the tower  100  with an upper end  10 A′ of the first vertical flat bar  10 A in abutting communication with a lower end  10 B′ of the second vertical flat bar  10 B. A joining plate  20  having a plurality of apertures  21  is attached to the first and second flat bars  10 A,  10 B, respectively, where the ends  10 A′  10 B′ abut. In this configuration, the ends  10 A′  10 B′ of the first and second vertical flat bars  10 A,  10 B are sandwiched between the exterior surface  102  of the tower  100  and the joining plate  20 . The joining plate  20  is attached to the tower  100  (with the flat plate bars sandwiched therebetween) using a plurality of bolts  160  preferably a plurality of one-sided splice plate bolts  160  and nuts  160 A. 
     Referring to  FIG. 1B , which shows attachment of abutting ends  10 A′ and  10 B′ and the joining plate  20 , a spacing  24  can exist between the upper end  10 A′ of the first vertical flat bar  10 A and the joining plate  20 . This spacing  24  occurs due to the prior art monopole&#39;s  100  construction namely, the overlap of the monopole&#39;s  100  sections that form the monopole  100 . When this occurs, a spacer plate  30  can be inserted within the spacing  24  between the outer surface of the vertical flat bar  10 A and the joining plate  20  such that the attached joining plate  20  is attached to a substantially level solid surface. 
     As best shown in  FIG. 1C , the tower  100  is affixed to the base flange  110  with means known in the art. The vertical flat bar  10 , when required, can be attached to the tower  100  so that a lower end designated as  10 C in  FIG. 1C  is positioned adjacent, but not in abutting relationship with, the base flange  110 . To further strengthen the tower reinforcement apparatus  1 , a full penetration weld  50  is disposed between the end  10 C of the vertical flat bar  10  and the base flange  110 . It should be noted that for safety measures, and other concerns relating to welding to monopole towers, the only welding operation when attaching the tower reinforcement apparatus  1  of the present invention is the weld  50  between the lower end  10 C of the vertical flat bar  10  and the base flange  110 . 
     The vertical flat bar  10  is selectively positioned along the length of the tower  100  in order to add support to that area of the tower  100  where additional communication equipment is to be installed. As discussed, multiple vertical bars  10  are preferably joined with joining plates  20  to maximize the strength and provide reinforcement to the tower  100 . In the preferred embodiment, a plurality of vertical flat bars  10  and joining plates  20  may be used in order to strengthen the approximate upper region of the tower  100  where added support is needed, as well as the approximate lower region of the tower  100  where added support is needed. Further, and as illustrated in  FIG. 2 , the preferred spacing between vertical flat bars  10  about the outer perimeter surface  102  of the tower  100  is approximately 120 degrees. As can be seen in cross-section  FIG. 2 , the monopole tower  100  is a  12  sided hollow column with each vertical flat bar  10  spaced  4  sides apart on one of the 12 flat sides of the tower  100 . 
     By installing multiple vertical flat bars  10  as described above, shorter lengths of flat bars  10  may be used for easier field assembly. As a result, it is possible to attach communication equipment and/or other types of loads directly to the tower  100 . Such loads may be attached to the tower  100  at any point along the vertical length of the installed tower reinforcement apparatus  1 . 
     By installing the tower reinforcement apparatus  1  to the tower  100  as described above, bending moments experienced by the tower  100  may be passed into and absorbed by the tower reinforcement apparatus  1 , thereby increasing the load capacity and stability of the tower  100  in order to enable the tower  100  to support the weight of additional communication equipment as well as the environmental forces exerted on the tower. 
     The tower reinforcement apparatus  1  may be installed on towers which are not yet installed or which is not vertical, or on previously installed towers. 
     Metal, such as steel or aluminum, is the preferred material of construction of the preferred embodiment of the vertical flat bars  10  and the joining plates  20 . 
     The preferred bolts  150 ,  155  and  160  are known in the art. The size of the bolts  150 ,  155  and  160  and spacing of the bolts  150 ,  155  and  160  is determined by the amount of reinforcing required. Further, the extent of reinforcing also determines the size and length of the vertical flat bars  10 . In the preferred embodiment, the vertical flat bars  10  are installed continuous up the length of the tower  100 . Again, this is accomplished by installing the joining plate  20  to the ends of abutting vertical flat bars  10 . 
     In operation, to reinforce an existing tower  100  to which additional equipment is to be added, a series of holes  105 , as shown in  FIG. 4  would be drilled along the length of at least one flat side of the tower  100 . The placement and spacing of the holes  105  could be designed based on the added load of the additional equipment. Typically 3 flat sides, spaced at approximately 120 degree spacings around the tower, would each receive holes  105 . 
     With the holes  105  in place, flat bars  10  with clearances  11  matching the spacing of holes  105  are placed against each flat side of the perimeter  102  of the tower  100  and are bolted to the tower using bolts. All of the holes  105  and  11  can be pre-drilled prior to placing the flat bars  10  in place or some of the holes  11 ,  105  might be drilled after the flat bars are in place. Most towers  100  are tall enough to require multiple sections of flat bar  10 . A first flat bar  10 A is placed and then a second flat bar  10 B is placed aligned with the first bar  10 A and with ends  10 A′ and  10 B′ adjacent to each other forming a joint space. In these cases a plate  20  is placed over the joint space to support it. A series of holes  21  are drilled through the plate  20  and bolts  160  secure the plate  20  to the end of bars  10 A and  10 B. Again, holes  21  can be pre-drilled or drilled at the time of installation. As shown in  FIG. 3 , the plate  20  can be pre-attached to one of the flat bars  10 A prior to installation. Once in place an end of the bottom most bar  10 A is welded to a base flange  110  of the tower  100 . 
     Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. 
     It will be obvious to those skilled in the art that modifications may be made to the embodiments described above without departing from the scope of the invention. Thus the scope of the invention should be determined by the claims in the formal application and their legal equivalence, rather than by the examples given.