Abstract:
A composite brace, strut, or link for any application requiring the transfer of a concentrated load uses a stepped insert at the lug end to distribute the applied loads into a composite structure formed of a stacked arrangement of internal and external plies of composite material. The manufacture of the brace, strut, or link is performed in a cost effective manner. The composite lay-up is done so that many individual parts can be cut from the initial multi-part assembly, allowing the economy of scale to lower fabrication costs of the individual manufactured parts. The structure provides a system whereby the concentrated load applied at the stepped inserts can be distributed into the composite material without any gapping or separation as would occur in a traditionally configured end fitting joint between a circular metallic bushing and the adjacent composite material interface.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based on U.S. Provisional Application No. 61/189,436, filed on Aug. 19, 2008, and entitled, “Advanced End Fitting Design for Composite Brace, Strut, or Link”, the disclosure of which is incorporated herein by reference and on which priority is hereby claimed. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to an advanced composite structure and manufacture of same. More particularly, the present disclosure relates to structure wherein a concentrated load can be efficiently transferred into and out of the composite structure. 
       BACKGROUND OF THE INVENTION 
       [0003]    There are many situations where a brace, strut, or link type structure is required for joining two adjacent structures or components to transfer a concentrated load between two points. The materials used in these applications have traditionally been metallic. Typically, these links have been machined, forged or cast. However, a metal link has a weight disadvantage when compared to a reinforced plastic composite link of equal function. Metal weighs substantially more than a comparative reinforced plastic composite structure. 
         [0004]    Historically, the cost associated with the manufacture of composite structures has been a concern in determining their use. Technological advances have decreased the cost associated with the manufacturing of composites and have made composite structures more competitive. 
         [0005]    The use of composite materials in aircraft primary structure has become widely accepted in the aircraft industry. Substantial weight savings have been achieved. For structures such as braces, struts, and links where concentrated loads are introduced at a single location on each end, the load transfer using composite materials has presented a significant issue for designers. 
       OBJECTS AND SUMMARY OF THE INVENTION 
       [0006]    An object of the present disclosure is to provide structure whereby concentrated loads can be efficiently transferred into a composite material without compromising the ability of the composite material to perform load transfer at the interface between the point of load application and the composite material. 
         [0007]    Another object of the present invention is to provide a brace at least partially formed from a composite material and end fittings in which a load placed on the end fittings may be efficiently transferred to the composite material. 
         [0008]    A further object of the present invention is to provide a composite brace, strut, link or other structure which is comparatively light weight yet strong to handle relatively high concentrated loads. 
         [0009]    Yet a further object of the present invention is to provide a method for manufacturing a composite brace. 
         [0010]    A still further object of the present invention is to provide a composite brace, strut or link which overcomes the inherent disadvantages of conventional metallic braces, struts and links. 
         [0011]    The present disclosure is intended to provide structure that incorporates an efficient method of transferring a concentrated load into a composite strut, brace, or link (collectively referred to herein as “brace”) by using a tailored or stepped insert. More specifically, a brace formed in accordance with the present invention includes one or more end fittings or inserts, which are preferably formed of a metallic material, and an intermediary or secondary structure formed from a composite material which is joined to the one or more end fittings. Each end fitting preferably has at least one outer surface which is stepped. The composite material structure engages the stepped surface of the end fitting and is joined thereto such as by bonding the metallic end fitting to the composite material. Preferably, the composite material may be formed from plies, preferably one ply resting on and engaging a corresponding step of the stepped end fitting or insert. The stepped end fitting or insert allows the introduction of both tensile and compressive loads in a manner that distributes the load uniformly to the composite material without overloading the bond between the metal end fitting and the composite material. The stepped end fitting is configured to transfer the load into the composite structure, while maintaining strain compatibility between the composite material and the stepped insert for both tensile and compressive loads. The configuration provides a method by which gapping between the metallic bushing and the composite material in a traditionally configured joint under axial loads, and the resultant failure of the composite matrix, can be avoided. 
         [0012]    The configuration of the stepped insert can be tailored to optimize the load transfer between the stepped insert and the composite structure to achieve maximum efficiency of load transfer. The unique “stepped” interface between the composite structure and the end fitting is optimized for each specific use. This structure can be applied to various composite strut, brace, and link cross-sections including among others: circular tubes, “I” sections, and various solid shapes. 
         [0013]    Of particular concern in fabricating the metal and composite matrix (e.g., the overall brace) is the cost of the composite material and the processes involved in the lay-up of the composite material. The cost of hand lay-up can be lowered by utilizing automated processes for both cutting and lay-up of the composite material in the assembly process. Using automated processes and other cost effective fabrication methods result in an affordable weight efficient product. 
         [0014]    The composite material can be laser cut into large sheets for use on a multiple strut assembly, and the stepped insert may be extruded in a single long length for use in a multiple strut assembly. The extruded length of stepped inserts may then be placed in a tool for holding in a precise position. The composite sheets may then be placed in the tool with the stepped inserts. The multiple strut assembly may then be cured and rough-cut into multiple individual braces. As a final step, the individual struts may have a final machining to remove unnecessary material. 
         [0015]    These and other objects, features and advantages of the present invention will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure, and together with a general description of the disclosure given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention. 
           [0017]      FIG. 1  is an exploded perspective view of a portion of a composite brace formed in accordance with the principles of the present invention and illustrating how the center core plies are mountable on the stepped insert of the composite brace. 
           [0018]      FIG. 2A  is a partially exploded perspective view of a portion of the composite brace of the present invention shown in  FIG. 1  and illustrating how the external plies of the composite brace are mountable on the stepped insert and center core plies. 
           [0019]      FIG. 2B  is a perspective view of a portion of the assembled composite brace formed in accordance with the present invention. 
           [0020]      FIG. 3A  is a perspective view of another embodiment of the composite brace formed in accordance with the present invention. 
           [0021]      FIG. 3B  is a perspective view of yet another embodiment of the composite brace formed in accordance with the present invention. 
           [0022]      FIG. 3C  is a cross-sectional view of the composite brace shown in  FIG. 3B  taken along line  3 C- 3 C of  FIG. 3B . 
           [0023]      FIG. 3D  is a cross-sectional view of the composite brace shown in  FIG. 3B  taken along line  3 D- 3 D of  FIG. 3B . 
           [0024]      FIG. 3E  is an exploded perspective view of portions of the composite brace shown in  FIG. 3B  and cut along line  3 C- 3 C of  FIG. 3B . 
           [0025]      FIG. 3F  is a perspective view of a bottom longitudinal portion of the composite brace of the present invention shown in  FIG. 3B  and cut along line  3 D- 3 D of  FIG. 3B . 
           [0026]      FIG. 3G  is an exploded perspective view of an internal or external ply used in forming the composite brace of the present invention. 
           [0027]      FIG. 4  is a perspective view of a stepped insert formed in accordance with the principles of the present invention. 
           [0028]      FIG. 5  is a perspective view of a composite brace assembly blank formed of external plies, stepped inserts and center core plies before cutting and final machining to form multiple composite brace in accordance with the principles of the present invention. 
           [0029]      FIG. 6A  is a top view of the composite brace assembly blank of the present invention shown in  FIG. 5  from which multiple composite braces are formed in accordance with the principles of the present invention. 
           [0030]      FIG. 6B  is a side view of the composite brace assembly blank of the present invention shown in  FIGS. 5 and 6A  from which multiple composite braces are formed in accordance with the principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    The composite laminate structure of the present invention provides an inexpensive lightweight brace for use in mechanical assemblies. Moreover, by providing a lightweight structure, the operating costs associated with the aircraft are decreased. 
         [0032]    Reference is now made to the drawings, in which like reference numerals identify identical or substantially similar parts throughout the several views. A single brace, link, or strut  10  is illustrated in  FIGS. 1-4  in accordance with one embodiment of the present disclosure. The brace  10  formed in accordance with the present invention comprises a series of flat inner composite plies  12  and at least one but preferably two stepped inserts  20  overlaid with another series of flat outer composite plies  14 . Each of the composite plies  12 ,  14  is preferably a subassembly of a plurality of individual ply layers  40  joined together, as shown in  FIG. 3G . 
         [0033]    A stepped insert  20  for use in an axially loadable, composite laminated structure is illustrated in  FIG. 4 . A series of graded steps  22  preferably symmetrically projecting from each opposite side of the main body  21  of the stepped insert  20  is provided for the introduction of tensile and compressive loads in a controlled fashion to the body of the composite structure. The height of each step is preferably equal to the thickness of each inner composite ply assembly  12 . A radiused (curved) outer portion  24  may define a side opposite the graded steps  22 . A hole or bore  28  projects through the body  21  of the stepped insert  20  between lateral sides  26  and equidistant from the top and bottom sides having steps  22 . The stepped insert  20  is symmetrical about the longitudinal plane. Each lateral side  26  of the stepped insert  20  is preferably, perpendicularly disposed to the longitudinal axis of the insert  20 , but may be concavely shaped when the brace  10  is in its finished state to exhibit an “I” in transverse cross-section, as shown in  FIGS. 3B and 3C . 
         [0034]    The stepped insert  20  is preferably made of Titanium. One way to make a close tolerance stepped insert while minimizing cost is to extrude the stepped insert. A bushing (not shown) may be placed in the hole  28  of the stepped insert  20  to minimize wear on the hole  28  when a bolt, rod or other structure is received thereby. In addition, the steps  22  preferably protrude a greater distance horizontally (longitudinally) than the height of the steps (i.e., the run is greater than the rise). 
         [0035]    With reference to  FIGS. 3A-3F , a brace  10  with two stepped inserts  20   a ,  20   b  is illustrated. The body of the brace  10  comprises inner plies  12  of graphite epoxy laminate using a lay-up of graphite epoxy pre-pregnated tape, or other material. External plies  14  may be wrapped around the perimeter of the inner plies  12  and stepped inserts  20   a ,  20   b  to carry tensile forces into the body of the composite laminated structure. The series of composite plies  12 ,  14  may also be a laminate of graphite and epoxy pre-impregnated tape. 
         [0036]    The center portion of the brace  10  is fabricated by cutting multiple preassembled plies and stacking the preassembled plies  12  from the part centerline to mate with each of the steps  22  on the stepped inserts  20   a ,  20   b , at each end of the brace  10 . This fabrication sequence is carried out with the aid of an assembly jig (not shown) in two stages. The outer external plies  14  are installed to complete the assembly using a lay-up of graphite epoxy pre-pregnated tape. To reduce costs further, the above assembly process is performed to create a wide section assembly consisting of many individual braces  10 , as shown in  FIGS. 5 ,  6 A and  6 B. 
         [0037]    The steps to creating many individual braces in an efficient, cost effective manner are as follows and as shown in  FIGS. 1 ,  2 ,  3 A- 3 F,  5 ,  6 A and  6 B. 
         [0038]    First, a series of composite plies  12  having the same width are cut into various lengths. Second, the stepped inserts  20   a ,  20   b  are placed into each end of a tooling fixture or assembly jig so that the stepped ends of the inserts  20   a ,  20   b  face one another. Third, the shortest of the series of composite plies  12   a  is placed between the stepped inserts  20   a ,  20   b  and in alignment with the most longitudinal extended stepped ends of inserts  20   a ,  20   b . As further described below, one side of the composite brace  10  (e.g., the top side) is assembled first, and then the second side (e.g., the bottom side) is assembled. Alternatively, both the top and bottom sides of the composite brace  10  may be assembled simultaneously. Fourth, the next shortest of the series of composite plies  12   b  is placed over each of the initial (first) top steps  22   a  of the stepped inserts  20   a ,  20   b  so that the longitudinal end portions of the ply  12   b  rest on and engage the surface of the corresponding first top steps  22   a , while the middle portion of the ply  12   b  rests on and engages the corresponding top surface of the first ply  12   a . Fifth, the next (third) shortest of the series of composite plies  12   c  is placed over each of the next (second) top steps  22   b  of the stepped inserts  20   a ,  20   b  so that the opposite longitudinal end portions of the ply  12   c  rest on and engage the surfaces of the corresponding second top steps  22   b , while the middle portion of the ply  12   c  rests on and engages the outer surface of the second ply  12   b . This step is repeated until the longest of the series of composite plies  12   n  is placed over the second most top ply  12   n - 1  below it and so that the opposite longitudinal end portions of the top ply  12   n  rest on and engage the surfaces of the corresponding highest top steps  22   n . Sixth, the tooling fixture is rotated so that the bottom of the composite brace  10  may be assembled by repeating the fourth and fifth steps described previously for assembly of the top side of the composite brace  10 . 
         [0039]    As mentioned previously, the top and bottom sections of the composite brace  10  may be assembled simultaneously. In such a manner, after the shortest of the series of composite plies  12   a  is placed between the stepped inserts  20   a ,  20   b , then two equi-length, next shortest of the series of composite plies  12   b  are placed over each of the initial (first) steps  22   a  of the stepped inserts  20   a ,  20   b  so that the opposite longitudinal end portions of the plies  12   b  rest on and engage the surface of the corresponding first steps  22   a , while the middle portions of the plies  22   b  rest on and engage the corresponding opposite top and bottom surfaces of the first ply  12   a . Then, two equi-length, next shortest of the series of composite plies  12   c  are placed over each of the next (second) top and bottom steps  22   b  of the stepped inserts  20   a ,  20   b  so that the opposite longitudinal end portions of the plies  12   c  rest on and engage the surfaces of the corresponding top and bottom second steps  22   b , while the middle portions of the plies  12   c  rest on and engage corresponding outer surfaces of the second top and bottom plies  22   b . This step is repeated until the two longest, equi-length plies  12   n  of the series of composite plies are placed over the top and bottom plies  12   n - 1  directly below it and so that the opposite longitudinal end portions of the top and bottom plies  12   n  rest on and engage the surfaces of the corresponding top and bottom highest steps  22   n  of the stepped inserts  20   a ,  20   b , while the middle portions of the plies  12   n  rest on and engage the corresponding outer surfaces of the top and bottom plies  12   n - 1  directly below it. 
         [0040]    Seventh, a series of external plies  14  are placed around the inner plies  12  and stepped inserts  20   a ,  20   b.    
         [0041]    Eighth, the composite laminated structure is vacuum bagged and cured. After being bagged and cured, the part is cut (see cut lines  35  in  FIG. 5 ) in depth D into smaller sections to form multiple individual braces  10 . Then, the individual braces  10  preferably undergo a finish machining to provide at least the middle portion of each composite brace  10  with an “I”-shaped cross-section and to complete the part. Finish cutting of the cured inner composite plies  12  and stepped inserts  20   a ,  20   b  is done to taper the width of the cured composite plies  12  and/or stepped inserts  20   a ,  20   b  toward the middle of the structure, such that the stepped inserts  20   a ,  20   b  and composite inner plies  12  and possibly outer plies  14  are wider at the ends than at the center. The tapering of the center section as shown in  FIGS. 3B-3F  is preferably done to reduce weight. 
         [0042]      FIGS. 5 ,  6 A and  6 B illustrate the brace assembly blank before it is cut into several braces. The inner plies  12  (also referred to collectively as the “core ply assembly”) are sandwiched between and surrounded by the external plies  14  (also referred to collectively as the “external ply assembly”), with the stepped inserts  20   a ,  20   b  positioned at opposite axial ends of the inner plies  12  and also sandwiched between and surrounded by the external plies  14 . The blank may be 12 inches in width, for example, and 12 inches in length measured between the centers of insert holes  28 , for example, as shown in  FIG. 5 . 
         [0043]    As will be appreciated from the detailed explanation provided below, the transfer of concentrated loads into the composite brace  10  can be successfully achieved without compromising the limitations of the composite plies  12 ,  14  at the stepped insert  20  interface with the adjacent attachment structure by using steps  22 . The brace described above and shown in one or more of the figures has been analyzed to be lighter than and as strong as an equivalently-sized aluminum brace. 
         [0044]    The distribution of load between the stepped insert  20  and the external plies  14  is dependent on the ratio of the Area×Modulus of Elasticity (AE) of the inner plies  12  and the Area×Modulus of Elasticity (AE) of the stepped insert  20  at the net section (A-A) (see  FIG. 3 ). The balanced load distribution is obtained by consideration of the load transfer capability of the plurality of steps  22  of the stepped insert  20  where the load in the stepped insert  20  is transferred to the inner plies  12 . This iterative process is used to obtain the optimum configuration defining the number and size of steps  22 , the thickness of the stepped insert  20  at the net section and the number of external plies  14 . The optimized configuration results in the efficient transfer of load with no gapping between the stepped insert  20  and the composite plies  12 ,  14 , thus maintaining joint integrity. 
         [0045]    Preferably, each step  22  of inserts  20  has an exposed surface used to introduce axial compressive loads to the inner plies  12  and by shear lag to the external plies  14 . Again as with the tensile case, no gapping between the stepped insert  20  and the inner plies  12  will occur, thereby preserving joint integrity. 
         [0046]    The use of the stepped insert  20  to efficiently transfer the concentrated load to the composite material  12 ,  14  is comparable generally in form to the material used for the lug of a conventional metallic end fitting and therefore no weight penalty is incurred as related to a conventional metal design. The weight advantage of the presently disclosed structure is primarily realized over the body of the brace or strut. 
         [0047]    To reiterate what was disclosed previously, a composite brace  10  formed in accordance with the present invention includes at least one stepped insert  20 , the at least one stepped insert  20  having an outer surface formed with a graded series of parallelly disposed steps  22 ; and a plurality of flat composite plies  12  formed of a composite material, each composite ply  12  having an outer surface and an axial end portion, the end portions of at least some of the composite plies  12  resting on and engaging corresponding steps  22  of the outer surface of the least one stepped insert  20 , the plurality of flat composite plies  12 , when mounted on the at least one stepped insert  20 , overlying one another in a stacked arrangement. In a preferred form, the at least one stepped insert  20  is formed of a metallic material, such as Titanium. Furthermore, the at least one stepped insert  20  of the composite brace  10  includes a main body  21  having opposite lateral sides  26 , and the main body  21  has formed therein a bore  28  passing therethrough between the two opposite lateral sides  26 . 
         [0048]    Even more preferably, each respective step  22  of the at least one stepped insert  20  has a predetermined height measured with respect to a next adjacent step. Furthermore, each composite ply  12  of the plurality of composite plies has a thickness which is at most equal to the predetermined height of each step of the at least one stepped insert  20 . 
         [0049]    In one form of the present invention, each composite ply  12 ,  14  of the plurality of composite plies is a subassembly of a plurality of individual ply layers  40  joined together. More specifically, each composite ply  12 ,  14  of the plurality of composite plies may be formed of a graphite epoxy laminate using a lay-up of graphite epoxy pre-pregnated tape. 
         [0050]    In an even more preferred form of the present invention, the composite brace  10  includes a first stepped insert  20   a  and a second stepped insert  20   b . The first and second stepped inserts  20   a ,  20   b  are spaced apart from each other. Each of the first and second stepped inserts  20   a ,  20   b  has an outer surface formed with a graded series of parallelly disposed steps  22 . Furthermore, each step  22  has a predetermined height. The first and second stepped inserts  20   a ,  20   b  are spaced apart from each other and disposed with their stepped outer surfaces facing each other. 
         [0051]    Also, the composite brace  10 , in this alternative form, includes a plurality of inner, flat composite plies  12  formed of a composite material. Each inner composite ply  12  has an outer surface and opposite axial end portions. The end portions of at least some of the inner composite plies  12  rest on and engage corresponding steps  22  of the outer surfaces of the first and second stepped inserts  20   a ,  20   b . The plurality of inner composite plies  12 , when mounted on the first and second stepped inserts  20   a ,  20   b , overlie one another in a stacked arrangement situated between the first and second stepped inserts  20   a ,  20   b.    
         [0052]    In an even more preferred form of the composite brace  10  described above, a plurality of outer, flat composite plies  14  formed of a composite material is included. The outer composite plies  14  are wrapped about at least a portion of each of the first and second stepped inserts  20   a ,  20   b  and overlie the inner composite plies  12  in a stacked arrangement. 
         [0053]    The present invention also relates to the structure of an end fitting  20  for use in a composite brace  10 . Such a composite brace  10  has a plurality of flat composite plies  12  formed of a composite material, where each composite ply  12  has an outer surface and an axial end portion, and a predetermined thickness. The end fitting  20  preferably includes a main body  21 , the main body  21  having an outer surface, and a graded series of parallelly disposed steps  22  formed in the outer surface. Preferably, each step  22  resides in a plane, and each step  22  has an outer step surface which is engageable by the outer surface of an axial end portion of a respective composite ply  12  such that, when the axial end portions of the plurality of composite plies  12  engage the parallelly disposed steps  22  of the end fitting  20 , the composite plies  12  overlie one another in a stacked arrangement. 
         [0054]    Again, in a preferred form, the end fitting  20  is formed of a metallic material, such as Titanium. 
         [0055]    In a preferred form, the main body  21  of the end fitting  20  includes opposite lateral sides  26 , and the main body  21  has formed therein a bore  28  passing through between the two opposite lateral sides  26 . Furthermore, each step  22  of the end fitting  20  preferably has a predetermined height on the outer surface of the end fitting measured with respect to a next adjacent step, the predetermined height being at most equal to the predetermined thickness of the composite plies  12 . Stated another way, the plane in which each step  22  respectively resides is spaced from the plane in which a step  22  adjacent thereto resides by a predetermined distance, the predetermined distance being at most equal to the predetermined thickness of a composite plies  12 . 
         [0056]    As also described previously, a method of manufacturing a composite brace  10  in accordance with the present invention preferably includes the step of cutting a plurality of inner composite plies  12  each having the same width into various lengths, each of the cut inner composite plies  12  having opposite first and second axial end portions and being formed of a composite material. Then, a first stepped insert  20   a  and a second stepped insert  20   b  are spaced apart from one another a predetermined distance to define a spacing therebetween. Each of the first stepped insert  20   a  and the second stepped insert  20   b  has a main body  21 , the main body  21  having a stepped outer surface and a graded series of parallelly disposed steps  22  formed in the stepped outer surface. Furthermore, each step  22  of each of the first stepped insert  20   a  and the second stepped insert  20   b  has an outer step surface, the first stepped insert  20   a  and the second stepped insert  20   b  being arranged with respect to each other such that the stepped outer surface of the first stepped insert  20   a  faces the stepped outer surface of the second stepped insert  20   b.    
         [0057]    The method of manufacturing the composite brace  10  further includes the step of placing the cut inner composite plies  12  having various lengths in alignment with the first stepped insert  20   a  and the second stepped insert  20   b  such that at least the first axial end portions of the cut inner composite plies  12  rest on and engage the outer step surfaces of respective steps  22  of the first stepped insert  20   a  and such that at least the second axial end portions of the cut inner composite plies  12  rest on and engage the outer step surfaces of respective steps  22  of the second stepped insert  20   b . The cut inner composite plies  12 , when placed on the first stepped insert  20   a  and the second stepped insert  20   b , overlie one another in a stacked arrangement bridging the spacing between the first stepped insert  20   a  and the second stepped insert  20   b.    
         [0058]    A plurality of outer composite plies  14  each having the same width and the same width as the inner composite plies  12  is cut into various lengths, each of the outer composite plies  14  being formed of a composite material. The cut outer composite plies  14  are placed on the first stepped insert  20   a  and the second stepped insert  20   b  and the stacked arrangement of inner composite plies  12  such that the cut outer composite plies  14  at least partially wrap around the first stepped insert  20   a  and the second stepped insert  20   b  and overlie the stacked arrangement of cut inner composite plies  12 . The cut outer composite plies  14 , when placed on the first stepped insert  20   a , the second stepped insert  20   b  and the stacked arrangement of cut inner composite plies  12 , overlie one another in a stacked arrangement. The first and second stepped inserts  20   a ,  20   b , the cut inner composite plies  12  and the cut outer composite plies  14  together define a composite laminated structure. 
         [0059]    Then, in accordance with a preferred method of manufacturing a composite brace  10 , the composite laminated structure is cured such that the cut inner composite plies  12  adhere to one another and to the first and second stepped inserts  20   a ,  20   b  and so that the cut outer composite plies  14  adhere to one another and to the first and second stepped inserts  20   a ,  20   b  to form a composite brace  10  having a middle section and opposite axial end sections. 
         [0060]    To reduce the weight of the composite brace  10 , the width of the composite brace may be tapered such that at least a portion of the middle section of the composite brace  10  is narrower in width than the opposite axial end sections of the composite brace. 
         [0061]    Also, in accordance with a preferred method of manufacturing the composite brace  10 , after curing the composite laminated structure, the composite laminated structure may be cut into smaller sections to form a plurality of smaller composite braces  10 , each of the smaller composite braces having a middle section and opposite axial end sections. Again, the width of each smaller composite brace  10  may be tapered such that at least a portion of the middle section on each smaller composite brace is narrower in width than the opposite axial end sections of each smaller composite brace  10 . 
         [0062]    Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments and that various other changes and modifications may be effected herein by one skilled in the art without departing from the scope or spirit of the invention.