Photos
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Downstream Elevation Showing Relationship Of Bridge To Surrounding Farms, Looking Sw Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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East Approach, Looking W Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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West Approach, Looking E Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Downstream Elevation, Looking S Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Upstream Elevation, Looking N Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Upstream 3/4 View, Looking Wnw Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Portal View Through Truss Showing Builders Plate, Looking E Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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View Through Truss Snowing Concrete Deck, Looking E Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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View Through Truss Showing Upper Chord, Top Lateral And Cross Bracing, Looking W Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Inclined End Post, Upper Chord Connection Point 1 (1l Near, 1r Far) Looking N Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Upper Chord Connection Panel Point 2l, Looking N Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Upper Chord Connection Panel Point 3, Looking N Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Inclined End Post, Lower Chord Connection And Abutment, Looking Nw Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Lower Chord And Connections At Panel Point 2l And 3 (1. Co R.), Looking N Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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South Elevation Showing Inclined End Post And Upper Chord Connection At Panel Point 1r, Lower Chord And Inclined End Post Connection, And Abutment, Looking Ene Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
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Underside Of Concrete Deck Showing Floor Beams, Stringers, And Cross Bracing, Looking W Photo by J. Ceronie, photographer, Bennett, Muessig & Associates, Ltd., Iowa City, IA, February 1983, for HAER |
Facts
- Overview
- Lost Pratt through truss bridge over Big Bear Creek on 33rd Avenue in Monmouth Township
- Location
- Monmouth Township, Jackson County, Iowa
- Status
- Replaced by new bridge
- History
- Built 1913; Replaced 1995
- Builder
- - Clinton Bridge & Iron Works of Clinton, Iowa
- Design
- Single span, six-panel summetrical Pratt through truss structure, with steel superstructure, riveted connections, concrete deck and concrete abutments.
"The Mill Rock Bridge was erected by Clinton Bridge & Iron Works, a major Iowa bridge contractor. It is locally significant as an early instance of the use of riveted connections and concrete deck in county bridge construction. These were among features which were to become standard in subsequent decades due to the establishment of the Iowa State Highway Commission and the Commission's enforcement of design standards for various kinds of crossings. Because the Mill Rock Bridge does not display all features associated with this standardization program, it may be considered an illustration of the transition from county to state control of local bridge design and construction.
"The Mill Rock Bridge was documented bu Bennett, Muessig & Associates, Ltd., Town City, Iowa, for the Board of Supervisors and County Engineer, Jackson County, Iowa, in 1983. The project team comprised of J. Ceronie, photographer; Matha B. Bowers, historian; and Bruce A. Hatms, photographic assistant."
` - Dimensions
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Total length: 101 ft.
Deck width: 14.6 ft.
- Approximate latitude, longitude
- +42.05556, -90.86111 (decimal degrees)
42°03'20" N, 90°51'40" W (degrees°minutes'seconds") - Approximate UTM coordinates
- 15/676987/4658157 (zone/easting/northing)
- USGS topographic map
- Baldwin, Iowa 15.678710.4658730
- Inventory number
- BH 37389 (Bridgehunter.com ID)
Sources
- J.R. Manning - thekitchenguy [at] sbcglobal [dot] net
- HAER IA-7 - Mill Rock Bridge