Riverbend Road Bridge

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Former US 29 Crossing of the Otter River

This relatively unassuming through truss bridge on an old alignment of US 29 is notable for its unusual configuration, despite being built to a standard plan of the Virginia State Highway Commission (predecessor to today's VDOT). The design is one that blends elements of both Pratt and Warren truss configurations, a hybridization that seldom occurs in truss bridges (Pratts and Warrens function on somewhat different principles). The structure itself is comprised of five sections, or panels, separated by vertical structural members. The 2nd and 4th panels follow the Warren design: two diagonal members comprise each section, and since they alternate in direction, they function as Warren diagonals (Pratt diagonals would be angled towards the center of the truss.) It should also be noted that the inner diagonals are the heaviest in construction. In the center panel, however, the diagonals are lighter in strength and intersect one another, forming an "X" between the vertical members, also of lighter strength. The light construction and angles of the diagonals here clearly indicate that this section functions as a Pratt panel as opposed to a continuation of the Warren configuration. Overall, while following the elements found in the two most prolific truss methods, this is clearly a nonstandard design, and with it crossing a relatively short distance, an unmodified Pratt or Warren could have sufficed. However, as it is a standard plan structure meant to carry a major highway, it is likely that the design was chosen for strength and economics, as opposed to uniqueness.

The bridge also features three approach spans, all of which follow the 1920s and 30s concrete tee beam template. The beams of this design are noted for their attractive curves just above the piers. The piers that support the truss bridge consist of two columns connected together by an arch. These piers lack the Neoclassical features that are found on the piers of the nearby Staunton River Bridge, suggesting that aesthetics were of less importance in a remote area. The tee beam spans feature the standard period concrete fence style railings, which were attached to all types of bridges in Virginia during the 20s and 30s. The pipe railings on the truss span are even simpler, to the extent that they provide no protection for the trusses. This was clearly a utilitarian structure and probably received no attention from motorists when it was initially constructed.

This bridge and Riverbend Road have not carried US 29 traffic since 1953, when a new Otter River bridge (also still in use for one-way traffic) and a straighter alignment were constructed. For this reason it has remained in good condition, despite receiving little maintenance due to its secondary road status. The National Bridge Inventory gives it 54.9% sufficiency rating, which may have been partly increased by the fact that it had a low average daily traffic county of 658 in 2006. Thus, in all likelihood it is not danger for replacement and will remain standing for years to come.

Facts

  • Year erected: 1927
  • Route Carried: Riverbend Road (Old US 29)
  • Crosses: Otter River
  • Location: Altavista, Campbell County, VA.
  • Design: Five-panel, riveted Warren/Pratt hybrid through truss main span; three curved concrete tee beam approach spans.
  • Inside width: 23 ft., two lanes
  • Length of main span: 122.1 ft. Total length: 234.9 ft.
  • National Bridge Inventory ID: 4334
  • Coordinates: 37° 8'20.28"N, 79°14'37.26"W

Pictures

  • Various oblique shots of the bridge.

  • Portal views

  • Left: the underside of the bridge. Right: a shot of a truss pier and approach spans.

  • Top chord connections.

  • L: The pipe-style railing attached to the truss. C: Fence-style railing on the tee-beam spans. R: One of the date of construction plaques.