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Bridge No: L04005

County Name : Houston

City/Township: Black Hammer Township

MINNESOTA IDSTORIC BRIDGE INVENTORY

Inventory Number: H U -~Lt-1 - 0 II

National Register Eligible: Yes

Critieria : C

Township: 102 Range: 07W Section: 30 N!..)-tJ£-Nf. Context : Historic Iron and Steel Bridges in Minnesota

Period of Significance : 1905-1947 UTM Coordinates: 15:603554:4829913

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Structural Data

Main Span Type : 302

number main spam : 01

number appr spans :

structure length : 43.00

deck width: 16.00

Historical Data

Year built : 1905

USGS Quadrangle : Spring Grove

Superstructure :

Substructure :

Floor/Decking :

Other Features :

Retains Integrity : Yes

single-spilll, steel, rigid-connected, 3-pane1, half-hip, Pratt pony truss

H-piling abutments with wood-plank backwalls and flared wood-plank wingwalls

wood deck carried by 6 rolled I-beam stringers and 2 outside channels bolted to top of floor beams

upper chord: 2 channels with cover plate and battens; lower chord: 2 angles with battens; verticals: 4 angles with V-lacing; diagonals: 2 angles with battens; bottom-lateral bracing: crossed single rods; floor beams: rolled 1-bearns bolted to superstructure; railings: 2 lines of angles bolted to truss webs; partial bridge plate on northeast endpost: " . . . IE ... E & IR .. . lET .. . 1905"

Contractor/Builder : Joliet Bridge and Iron Company, Joliet, illinois

Designer : Joliet Bridge and Iron Company, Joliet, Illinois

Statement of significance :

Located in rural Black Hammer Township in southwestern Houston COWlty, Bridge No. L04005 carries an abandoned. dirt, township-owned road across Riceford Creek about three miles north and west of Spring Grove. The 41-foot span is a rigid-connected, steel, three-panel, half-hip, Pratt pony truss on steel H-piling abutments with plank backwalls and flared plank wingwalls. The two truss webs are identically detailed. Two channel sections with cover plate and battens form the top chord, while two angle sections with battens comprise the lower chord. Vertical members consist of four angle sections with V-lacing; diagonal members are paired angle sections with battens. The wood deck rests on eight rolled stringers (six I-bearns and two outer channel sections) bolted to the top flanges of rolled 1-beam floor beams, which, in tum, are bolted to the superstructure. Bottom-lateral bracing consists of crossed rods. A portion of a metal plaque remains on the bridge's northeast endpost, bearing the following inscription: • . . . IE .. . E & IR ... lET ... 1905. • The plaque reveals that the bridge was the work of the Joliet Bridge and Iron Company of Joliet, Illinois. The bridge's H-piling abutments indicate that the original substructure has been rebuilt, possibly because the superstructure was moved to its present site from another location. Since early twentieth-century trusses were designed to be relocated if necessary, this circumstance does not affect Bridge No. L04005's historical integrity.

In 1913, the Minnesota Legislature approved a series of measures that gave the Minnesota Highway Commission control of almost all highway bridge design in the state. A proponent of standardized bridge construction, the commission prepared a comprehensive set of plans and specifications that mandated the use of specific bridge types for specific

Hess, Roise and Company, Minneapolis. MinnesoliJ

MINNESOTA IDSTORIC BRIDGE INVENTORY

span lengths, defined acceptable and unacceptable detailing practices, and prescribed construction procedures for both steel and concrete structures. Periodically updated, until superseded in the late 1920s by similar guidelines issued by the American Association of Highway Officials, the Minnesota Highway Conunission's regulations for highway bridge construction ushered in an era of design unifonnity that lasted for the remainder of the twentieth century.

Before 1913, Minnesota highway bridge construction was largely in the hands of municipal, township, and county governments. Although a few counties and cities had professional engineers on staff to prepare bridge plans and superintend construction, most local governments acquired highway bridges through a process of competitive bidding by private bridge-building firms, which tailored their designs and construction practices to suit the expectations and finances of their clients, as much as to satisfy the physical demands of the site and the functional requirements of traffic. The result was a wide variety of bridge designs, some well engineered and some not. Over the years, the vast majority of these "non-standard" bridges were eventually replaced by state-designed structures, but a few still survive. Bridge No. L04005 is among the survivors.

Research in state and county archives failed to uncover infonnation concerning the construction of Bridge No. L04005. As evidenced by inspection reports on file with the Houston County Highway Department, the structure has been on its present site at least since the early 1970s. The bridge's northeast endpost bears a fragment of a metal builder's plaque, inscribed as follows: " ... IE ... E & IR ... lET . . . 1905." This inscription indicates that the bridge was originally designed and constructed in 1905 by the Joliet Bridge and Iron Company of Joliet, Illinois. Operating in the Midwest since at least the late 1890s, Joliet Bridge and Iron was responsible for building a number of steel pony trusses in southern Minnesota during the first two decades of the twentieth century. In addition to five bridges in Houston County, six other examples of the firm's work have been identified in Brown, Cottonwood, Faribault, Nobles, and Watonwan counties. In its design of Bridge No. L04005, Joliet Bridge and Iron employed a Pratt pony truss variant known as the "half hip" configuration, so-called because the truss webs omitted the customary vertical member at the hip position. Because the half-hip design used less steel than the conventional Pratt pony truss, it was cheaper to produce, which made it popular with economy-conscious township and county governments. Like other surviving Minnesota examples of Pratt pony trusses designed by Joliet Bridge and Iron, Bridge No. L04005 has rigid connections, which were preferred over pin connections by many "Good Roads" advocates because the resulting truss web appeared to be sturdier under live load. However, even rigid-connected, half-hip, Pratt pony truss were unsuitable for the increasingly heavier traffic loads of the twentieth century. When the Minnesota Highway Commission published its first bridge specifications, it prohibited the use of the design by requiring that all future pony-truss construction employ a rigid-connected Warren configuration.

The earliest and longest of the surviving half-hip Pratt pony trusses built by Joliet Bridge and Iron Company in Minnesota, Bridge No. L04005 is the state's best example of the firm's work with this particular bridge type. It is eligible for the National Register under Criterion C in the area of engineering, within the historic context of "Historic Iron and Steel . Bridges in Minnesota." The Multiple Property Docwnentation Form associated with this context states, under Registration Criterion 5, that a bridge may be eligible for the National Register if it was built by a company that was "very important to the construction of bridges in Minnesota." As an excellent example of the work of Joliet Bridge and Iron Company, Bridge No. L04005 satisfies this criterion.

References : Minnesota Department of Transportation Bridge Database; Bridge No. L04005 File in Minnesota Department of Transportation, Waters Edge Building, Roseville; Bridge No. L04005 File in Houston County Highway Department, Caledonia, Minnesota; "An Act Relating to Public Highways" (Chapter 235), General Laws of the State of Minnesota · · · 1913 (St. Paul: The Pioneer Company, 1913 ), 290-329; Minnesota Highway Commission, Report, 1912-1913, 9-ll ; Minnesota Highway Commission, Standard Specifications for Steel and Concrete Highway Bridges, 1912; Houston County Board of Commissioners, Proceedings, 1905, in Houston County Courthouse, Caledonia; Robert M. Frame, "Historic Bridge Project: A Report," prepared for the State Historic Preservation Office of the Minnesota Historical Society, and the Minnesota Department of Transportation, 1985, 81; Fredric L. Quivik. "Iron and Steel Bridges in Minnesota," Multiple Property Documentation Form, 1988, Sec. F, 9, in State Historic Preservation Office, Minnesota Historical Society, St. Paul; field inspection by Demian Hess, 26 October 1995.

Form Prepared By : Jeffrey A. Hess

Hess, Roise and Company, Minneapolis, Minnesota