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Table of Contents

List of Figures



History of Oklahoma Highway Bridges

The Historic Bridges of Oklahoma
Steel Truss Bridges
• King Post Pony
• Small Pratt (3 panel) Pony
• Truss Leg Bedstead Pony
• Pratt Pony
• Pratt Half-Hip Pony
• Parker Pony
• Camel Back Pony
• Warren w/ Verticals Pony
• Warren w/ Polygonal Top Chord Pony
• Warren Bedstead Pony
• Double Intersection Warren Pony
• Pratt Through
• Modified Pratt Through
• Parker Through
• Camelback Through
• Modified Parker Through
• Warren Through
• K-Truss
• Deck Truss
• Mixed Truss

Concrete and Stone Bridges
• Concrete Arch
• Rainbow Arch
• Stone Arch





    1902	Kay		36E0270N3250005	  American Br.
    1907	Payne		60E0590N3170009	  Joliet Br.
    1908	Harper		30E0030N1810009	  Canton Br.
    1910	Comanche	16E1650N2360001
    1910	Comanche	16E1560N2640005
    1910	Creek		19N3630E0640009	  Missouri Valley Br.
    1911	Kay		36E0040N3220006	  Canton Br.
    1912	Washington	74N4040E0005009	  Rochester Br.
    1915	Blaine		06N2640E0620008	  Canton Br.
    1915	Kay		36N3210E0090006	  Canton Br.
    1919	Pawnee		59E0520N3580009
    1927	Pawnee		59E0530N3580009	  Central Const.
    1932	Creek		19E0750N3750002	  Vincennes Br.

  Bridge engineers constantly looked for ways to reduce the cost of steel bridges without also diminishing their strength or longevity.  The inherent qualities of the Pratt configuration invited this experimentation and led to new variations, such as the Pratt half-hip pony.  In this design the hip vertical--the first vertical member beyond the end post--is eliminated and the end post made more perpendicular, thereby simplifying the structure and requiring less metal.  Bridges of this kind sold for less, and Oklahoma countiew made it a popular choice; 129 remain as evidence of their extent in earlier times.
  Half-hip Pratts came from the shops of companies well represented in the state sa builders of trusses, among them the Canton Bridge Company, which often identified theirs with a nameplate that covered the joint at the end post.  The same distinctive coverplate was used by the Central Concrete and Construction Company, very likely an affilate of Canton Bridge (Figure 50).  The oldest documented half-hip pony spans a creek southwest of Tonkawa in Kay County.  The county acquired the 59-foot bridge in 1902 from the American Bridge Company of New York, then a recently formed consolidation of builders put together by banker J. P. Morgan that ws labeled the "bridge trust."  Over Stillwater Creek in Payne County stands the only example of a span fabricated by the Joliet Bridge and Iron Company of Joliet, Illinois, that did not often build in the Southwest.  Blaine County has an unusual two span half-hip, each 50 feet in length, with pins and rivets, that dates from about 1915, somewhat late for using this type (Figure 51).

Figure 50.  The distinctive coverplate and finial on Bridge 59E0530N3580009 indicates a tie-in between Canton Bridge Company and the Central Concrete & Construction Company of Canton, Ohio.  The Pratt half-hip is located on Ranch Creek two miles west of Hallett.

Bridge 06N2640E0620008, located near Okeene, is an uncommon two span Pratt half-hip pony truss.
  Bridge 60N3300E0530009, a rare example of a truss biult by the Wichita Construction Company, is a 1910 Pratt pony span.

  Figure 51.
  Bridge 06N2640E0620008,
  located near Okeene, is an
  uncommon two span Pratt
  half-hip pony truss.

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