Description
The Hares Hill Road Bridge is a single span, 103’-4” long, wrought-iron, arch-shaped lattice girder structure. It was built in 1869 in Chester County, Pennsylvania, by Moseley Iron Bridge and Roof Company. Abraham Taney, Jr., a mason contractor and fabricator, erected the bridge abutments in 1869. Stone masonry abutments support the superstructure and the open grid deck. Over the years, the bridge has had extensive rehabilitations.
The structure is listed in the National Register of Historic Places and has a high degree of historical and technological significance: it is the only known surviving example of Thomas William Moseley’s patented "Wrought Iron Lattice Girder Bridge." The bridge has been recorded for the Historic American Engineering Record (HAER) with detailed drawings, photographs and a substantial historical narrative. The structure carries one lane of traffic on Hares Hill Road (unsigned State Route 1045) across French Creek. Residences are located along the north bank of French Creek and a wooded area runs along the south bank.
The abutments are founded on rock and consist of random rubble mortared sandstone. They are 20 feet (6.1 m) long, 7 feet (2.1 m) wide at the base, have a batter of 1/2 inch to the foot, and are about 12 feet (3.7 m) high above low water. Concrete pedestals have replaced the original stone-bearing seats. Wing walls extend approximately 60 feet (18 m) with a slight flare on the south side. The north wings are about 20 feet (6.1 m) long.
The original superstructure consisted of the 2 wrought-iron arched girders with lattice webbing and a timber floor system. The arch girders are made up of a pair of “Z-bars” riveted to a central plate diaphragm. Diagonal latticing fills the web between the upper and lower portions of the plate. Each arch has 7 vertical members which support the floor system, along with the lattice and bottom tie plate. Bowstring-type tie rods extend diagonally from the bottom of the center vertical on both sides of each arch.
The HAER narrative cites 3 major rehabilitations to 1991.
While the bridge is currently painted yellow, it was painted silver for many years and local residents still refer to it as the “Silver Bridge.”
In 2009, PennDoT was programmed to spend $1.7 million to rehabilitate this bridge to improve its load capacity without interfering with its historical nature. On, 22 June 2010, the bridge was closed for the rehabilitation work. The US$826,689 restoration project is expected to last until October. The project will replace the open grate deck and the new deck will have a concrete center section for bicycle use. When completed, the load restriction is expected to be raised to 15 tons (14 metric tons).
The Hares Hill Road bridge is scheduled to reopen on Friday December 10, 2010 according to PennDOT Press Release.
Read more about this topic: Hares Hill Road Bridge
Famous quotes containing the word description:
“It [Egypt] has more wonders in it than any other country in the world and provides more works that defy description than any other place.”
—Herodotus (c. 484–424 B.C.)
“He hath achieved a maid
That paragons description and wild fame;
One that excels the quirks of blazoning pens.”
—William Shakespeare (1564–1616)
“The great object in life is Sensation—to feel that we exist, even though in pain; it is this “craving void” which drives us to gaming, to battle, to travel, to intemperate but keenly felt pursuits of every description whose principal attraction is the agitation inseparable from their accomplishment.”
—George Gordon Noel Byron (1788–1824)