For Christmas I received a PRR signal in HO scale from Z-Stuff for trains. It is the model DH-1060 HO. I installed the signal on my small bedroom layout which depicts Conrail's Allegheny Industrial track from Oakmont to Verona, PA. Essentially, it is a brass NJ International signal with a sensor and circuitry attached. Installation is very simple. All that is required is a 1/2 inch hole for the circuit board to fit in and a connection of two wires to a DC power pack. The signal isn't connected to any dispatching system, but operates independently. As per a real PRR position light block signal, the model displays a clear vertical indication when it doesn't sense a train next to it. When a train is detected, the indication changes to a horizontal stop. After the train has passed, the signal displays a caution diagonal indication on its way to displaying a clear indication again. See the pictures below for more detail. Happy New Year!
Well, it's been a long time in the making, but the new Greensburg Pike Bridge in Turtle Creek is finally open to traffic. It may seem a little crazy, but the bridge it replaced seemed like an old friend. It had been there my entire life and I can remember riding across it since I was a young boy. Officially known as the Greensburg Pike Bridge, I always just referred to it as the "Blue Bridge."
The web site www.pghbridges.com provides a lot of facts about the old bridge. It was built in 1925, connecting Turtle Creek Borough on the north end to North Versailles Township on the southern end. It was a four span Pratt through-truss bridge, measuring 845' long. It crossed Turtle Creek and the former PRR (now NS) main line, as well as an industrial spur track that led to the former Westinghouse facilities.
This Hopkins map from 1903 shows the alignment of the predecessor bridge, which matched the street grid network of Turtle Creek. The bridge was adjacent to the Turtle Creek passenger station, located on the southern side of Turtle Creek, and it allowed the major east-west roadway to cross the creek and the railroad tracks. This road, known as the Greensburg Pike, would become part of the coast-to-coast Lincoln Highway.
In 1925, a new, longer bridge was built by Allegheny County with a skewed alignment in order to eliminate the sharp turns at each end. It followed the alignment of the road on its southern end and met Penn, Monroeville and Airbrake Avenues at a signalized intersection on its northern end. This bridge was to last 88 years! www.historicbridges.org grandly refers to this bridge as the "Great Valley Bridge." This web site notes "The bridge should also be considered historically and technologically significant as a relatively complex bridge, since its skew, incline, and multi-span configuration are indicative of a more complicated and noteworthy engineering achievement." I couldn't have said it better myself! It had two 12-foot lanes and a sidewalk along its western edge. The reported average daily traffic count is 6,908 vehicles. www.bridgemapper.com also states that this bridge "is historically significant because it was built as a joint project between Allegheny County and the Pennsylvania Railroad, dating from a time where industrialization necessitated such transportation improvements."
The new bridge allowed easy access to George Westinghouse's vast industrial empire stretching for two miles along Turtle Creek from East Pittsburgh to Wilmerding, but as the automobile became more commonplace, it also carried a significant amount of through traffic on the Lincoln Highway. www.pghbridges.com states that the through traffic and bustling activity in the valley at times created an hour delay in traversing the valley! It was soon apparent that the highway needed to bypass the industrial valley and Allegheny County began design and construction of the George Westinghouse Bridge to carry the Lincoln Highway, now called US Route 30, across rather than through the valley.
The "Blue Bridge" had last been rehabilitated in 1978-79, which included sandblasting and a new coat of paint. Even with this work, vehicle weight limits had been reduced from 22 to 11 tons and the overhead steel members limited the vertical clearance to 13.0 feet. Clearly, this bridge was obsolete. After more than a decade of planning, a design was approved to replace the bridge at a cost of around $20 million. Work started in September 2011, with the new bridge to be built adjacent to the old bridge so it could remain in service as long as possible. Knowing its days were numbered, Charlie and I paid a visit to the old bridge in July 2012 to get some photos before it was gone.
If room allows, we hope to model at least part of the old bridge on the Pittsburgh Mainline layout.
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