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Table of Contents

List of Figures

Acknowledgements

Introduction

History of Oklahoma Highway Bridges
• The Earliest Roads and Bridges
• The Drive For Good
Roads

• A New Era in Bridge Building
• The State Road System and Federal Aid
• The Shifting Direction of Bridge Building
• The Strains of Depression and War
• Meeting New Challenges Since WWII

The Historic Bridges of Oklahoma

Endnotes

Bibliography

Appendices




The Shifting Direction of Bridge Building

Throughout the 1920s steel truss bridges remained popular choices for ordinary highway spans.   Mass produced and fitting the standard specifications established by the highway department, they proved themselves economical and reliable structures; sensible choices because they cost less to buy and install on the site.  At places that required shorter spans, the practice in Oklahoma started to change about 1915, moving away from pin-connected Pratt pony trusses, including common variations such as the half-hip and truss leg bedsteads, to what remains today the most commonly found truss bridge in the state, the riveted Warren pony, with vertical members added for greater strength.  One reason for the low cost of this type was its simplicity;it was easily transported by rail or truck, with the main parts of its assembly already shop-riveted, and it could be installed by a crew of workers with minimal skill or little previous experience (Figure 31). Even in view of this the concrete pile trestle gained wider use at the time as an alternative to smaller steel bridges.41
  To meet the need for longer spans and heavier duty, the Pratt through truss generally lost favor to the Parker through truss at lengths greater than 120 feet.  This structure used a Pratt design as well, but its curved top chord made it possible to achieve greater length without sacrificing structural strength.  Somewhat attenuated in form, the Parker would in turn be tested by heavier and faster moving vehicles, eventually leading to its replacement by stronger designs.
  Better design and construction technology also explained the replacement of the pin-connected Pratt through truss which once had been the structure of choice in lengths of 80 to 120 feet.  



A crew erecting a new truss bridge stops long enough to pose for the photographer.
Figure 31.  A crew erecting a new truss bridge stops long enough to pose for the photographer.

Figure 32.  Building Bridge 1918 0139 X, a concrete arch, in downtown drumright in 1918. (Western History Collections, University of Oklahoma Library).


Figure 33.  Bridge 26E1330N2890002 is a Luten-type concrete arch located northeast of Chickasha.

Building Bridge 1918 0139 X, a concrete arch, in downtown drumright in 1918. (Western History Collections, University of Oklahoma Library).

Bridge 26E1330N2890002 is a Luten-type concrete arch located northeast of Chickasha.



During the 1920s highway department engineers decided that the camelback pony truss, having the compressive and tensile qualities of the Pratt but utilizing a distinctive five-angled top chord that gave the structure its name, was a superior design for standard use.  Strong and durable with its riveted joints, the camelback truss became a common feature on federal aid roads during the 1930s and into the 1950s.  When U. S. Route 66, the main road between Chicago to Los Angeles, began to extend across Oklahoma in the late 1920s under the sponsorship of its chief promoter, chairman of the state highway commission Cyrus Avery of Tulsa, engineers frequently specified camelbacks.  Even though one of America's most famous bridge engineers, J. A. L. Waddell, declared the design "uncompromisingly ugly," the camelback had qualities to recommend it.42  Versatile, it could be used in combination with other trusses and often was mated with large K-trusses on main routes, and by joining several together they could supplant larger and more costly structures.  With so much of the design based on common structural shapes and standard shop practices the camelback was widely available.  Its value in Oklahoma shows in the Red River bridge near Waurika, built in 1939 by the Virginia Bridge Company of Memphis, Tennessee, from twenty-one 100-foot camelback spans.  The result is an imposing structure, as though the whole exceeds the sum of the parts (Figure 53).43
  By the 1920s, while Oklahoma made more bridges out of concrete, reflecting national trends, it did not build concrete arches as extensively as did many other states at the time.  Reinforced concrete had the widest use in the building of small slab and beam bridges along with multitudes of culverts used as drainage structures.44  But the longer span concrete arch deck bridges (80 to 120 feet long) that appeared in growing numbers in the 1920s did not attain the predominance expected of concrete considering its usual selling points of lower cost and greater availability.  Concrete construction in Oklahoma faced some handicaps: concrete bridges proved more expensive than steel trusses for lengths greater than 70-feet; in many places, aggregates had to be shipped over long, costly distances; the presence of alkali in some areas imposed limitations; and, allegations were made at various times that the state suffered from overcharging at the hands of a "cement trust."45  Also, the skilled labor to build concrete arches may have been scarce at times (Figure 32).  Still the Topeka Bridge and Iron Company constructed a number of concrete arches in the state using the patented designs of engineer Daniel Luten.  Although thousands of Luten concrete arches were built around the country, nearly constant legal disputes about the patents may have made made some counties leery of these structures (Figure 33).



A picture postcard view of Bridge 74E0188N3950005, the Washington County Memorial Bridge over the Caney River.
Figure 34.  A picture postcard view of Bridge 74E0188N3950005, the Washington County Memorial Bridge over the Caney River.

Bridge 72E0600N3960002, the 21st Street Bridge in Tulsa. (Phillip Radcliffe photo, <i>Celebration Magazine</i>, 1983)
Figure 35.  Bridge 72E0600N3960002, the 21st Street Bridge in Tulsa. (Phillip Radcliffe photo, Celebration Magazine, 1983)



  These problems aside, the state added some noteworthy concrete structures during the 1920s and early 1930s.  In 1925 Ernest S. Alderman, a bridge engineer once employed by the Bureau of Public Roads and the Oklahoma State Highway Commission, built a 100-foot semicircular concrete arch over Pennington Creek in Tishomingo.46  A classical balustrade added to its attractiveness.  Equally striking in appearance because of its open spandrel arch and stylized railing, the 7th Street Bridge (Figure 34) over the Caney River in Bartlesville remains a premier example of concrete construction from an era noted for its craftsmanship.  The choice of the Kansas City Bridge Company for this project in 1923 was unusual since the company had an excellent reputation as a fabricator of steel trusses but almost none as a builder of concrete arches.47  Some years later Oklahoma acquired its longest concrete bridge (1,880 feet) when Tulsa raised funds through a bond issue to build a twenty-one span, open spandrel arch bridge across the Arkansas River.  The 21st Street Bridge, completed in 1932, opened a major new thoroughfare between downtown and fast growing western suburbs (Figure 35).



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