Keowee Street Bridge

Information and Findings From Ohio's Historic Bridge Inventory

Setting/Context

The bridge carries a 4 lane street and sidewalks over the Great Miami River in Dayton.

Physical Description

The 5 span, 490'-long, reinforced-concrete arch bridge has concrete balustrades that have panels alternating between open balusters and solid incised-panels. The spandrel walls are paneled as are the pilasters over the bullnose piers. There are shadow lines accenting the arches.

Integrity

Some loss of original fabric from spalling.

Summary of Significance

The 1931 deck arch bridge is a late but complete multiple-span example of its type/design with typical detailing. There are no innovative or distinctive details, and although it is multiple span, there are numerous earlier and better detailed examples in the county and region. The bridge is not historically or technologically significant. The 2007-08 ODOT Historic Bridge Inventory Update (Phase 1A) has identified more than 225 extant, reinforced-concrete, closed-spandrel arch bridges dating from 1896 to 1959. Fewer than 30 examples date to before 1910. Those tend to represent innovative technology or early attempts at exploring the aesthetic qualities of the moldable material; earlier examples tend to have higher historical and technological significance than the later examples. Use of the reinforced-concrete, closed-spandrel arch technology reached its height during the 1910s and 1920s with more than 80% of Ohio's surviving examples dating from those two decades. The later examples generally do not represent innovative technology, although they sometimes have high aesthetic merit or significant settings/contexts. "Closed spandrel arch bridges are the most basic of reinforced concrete bridge types. Closed spandrel means that the area between the deck and the arch ring was filled in. The spandrel wall actually serves as a retaining wall in the bridge, holding the fill material. Live loads are borne by the fill material and by the spandrel walls. The arch may be constructed either as a single structural element (barrel) or in separate parallel longitudinal ribs. The barrel arch design has some structural and visual similarities to stone arch bridges. The barrel arch is also sometimes faced with brick or stone, making it appear similar to a masonry arch bridge. This type of bridge is suitable for short span lengths. Closed spandrel concrete arches predate open spandrels, as the closed spandrel type harkens back to the stone arches that the earliest forms imitated. This type was not built for long as engineers realized that significant material could be saved and a reduction in weight could be achieved by eliminating the filled section. Hence, open spandrels were born. Filled spandrel concrete arches date primarily from the earliest decades of reinforced concrete (1890s through 1920s). They are not as common as many of the standardized bridge types built during this same era, such as concrete slabs and girders. They are significant because they are not common and represent the evolution of concrete technology. To be considered significant, filled spandrel arches should have integrity, through the retention of their character-defining features: arch ring, barrel, spandrel wall, railing or parapet, end posts, piers and/or abutments and wingwalls." [From: A Context for Common Historic Bridge Types by Parsons Brinckerhoff, October 2005]

Bridge Considered Historic By Survey: No