Walnut Street Bridge (Philadelphia, Pennsylvania)
Encyclopedia
The Walnut Lane Memorial Bridge is a prestressed concrete
girder bridge
in Philadelphia, Pennsylvania
, designed by Belgian Engineer Gustave Magnel and built by the City of Philadelphia. Completed and fully opened to traffic in 1951, this three-span bridge carries Walnut Lane over Lincoln Drive and Monoshone Creek. It was the first major prestressed concrete beam bridge designed and built in the United States when completed.
The form of the bridge is simple and appears to be like many highway bridges carrying traffic on US highways. The bridge deck is supported by thirteen concrete girders, each spanning 160 feet. These girders were prestressed by post-tensioning four wire cables embedded in the concrete. Although this type of construction had been used in Europe for quite some time, the Walnut Lane Memorial Bridge was innovative in the United States and led to the successful application of this technology in this country. The material-saving bridge cost about $700,000 to construct—about 30 percent cheaper than a regular concrete arch design.
A bronze plaque on the bridge's abutment reads:
A second plaque reads: "Outstanding Civil Engineering Achievement / Designated May 1978"
Prestressed concrete
Prestressed concrete is a method for overcoming concrete's natural weakness in tension. It can be used to produce beams, floors or bridges with a longer span than is practical with ordinary reinforced concrete...
girder bridge
Girder bridge
A girder bridge, in general, is a bridge built of girders placed on bridge abutments and foundation piers. In turn, a bridge deck is built on top of the girders in order to carry traffic. There are several different subtypes of girder bridges:...
in Philadelphia, Pennsylvania
Philadelphia, Pennsylvania
Philadelphia is the largest city in the Commonwealth of Pennsylvania and the county seat of Philadelphia County, with which it is coterminous. The city is located in the Northeastern United States along the Delaware and Schuylkill rivers. It is the fifth-most-populous city in the United States,...
, designed by Belgian Engineer Gustave Magnel and built by the City of Philadelphia. Completed and fully opened to traffic in 1951, this three-span bridge carries Walnut Lane over Lincoln Drive and Monoshone Creek. It was the first major prestressed concrete beam bridge designed and built in the United States when completed.
The form of the bridge is simple and appears to be like many highway bridges carrying traffic on US highways. The bridge deck is supported by thirteen concrete girders, each spanning 160 feet. These girders were prestressed by post-tensioning four wire cables embedded in the concrete. Although this type of construction had been used in Europe for quite some time, the Walnut Lane Memorial Bridge was innovative in the United States and led to the successful application of this technology in this country. The material-saving bridge cost about $700,000 to construct—about 30 percent cheaper than a regular concrete arch design.
A bronze plaque on the bridge's abutment reads:
| WALNUT LANE MEMORIAL BRIDGE Dedicated November 11, 1950 Opened to Traffic February 1, 1951 The First Prestressed Concrete Girder Bridge Built in the United States This structure is symbolic of the integrity and ability of the engineers and builders who during sixty six years – 1885-1951 – of Public Works Administrations, constructed many worthy projects for the City of Philadelphia. It is an outstanding example of the vision and courage these men showed in their planning and building. Bernard Samuel Mayor of Philadelphia |
A second plaque reads: "Outstanding Civil Engineering Achievement / Designated May 1978"
External links
- Walnut Lane Memorial Bridge at Historic American Engineering Record.
- Listing at Philadelphia Architects and Buildings