The Case of the Missing Ramps Solved in ’Burgh

Fri April 03, 2009 - Northeast Edition
Jennifer Rupp




The I-79 Parkway West ramps were opened for use in December 2008 after two years of construction. The two “missing” ramps will allow motorists direct access to the existing interchange of I-79, SR 22/30 and the Parkway West of Pittsburgh.

Since the 1970s, travelers have been directed onto Route 60 at the Crafton exit in order to reach the Pittsburgh International Airport. Traffic could not travel from southbound I-79 to Route 22/30 outbound, nor from inbound Route 22/30 to northbound I-79.

In August 2007, the Pennsylvania Department of Transportation (PennDOT), District 11, opened construction bids for the project. The lowest bid of $67.4 million was from Balfour Beatty Construction of Canonsburg, Calif. The final contract amount was $69.5 million.

The bulk of the project was the construction of the two “missing ramps” (labeled Ramp G and Ramp H) connecting I-79 to the Parkway West (I-279/Route 22/30). In addition, the project called for two new bridge structures, extension of an existing culvert, and two new retaining walls. The walls are 965 ft. (294 m) and 120 ft. (36.6 m) long, both using galvanized steel beams embedded in concrete caissons.

To achieve an acceptable level of service with the new ramps, a supplementary lane was added to the parkway in each direction. Furthermore, over a mile of the existing parkway was shifted up to 50 ft. (15.2 m) to make room for the additional lanes. This will reduce congestion on the parkway, increase merge safety and also increase overall driver safety.

Michael Baker Jr. Inc. was hired as the design team. According to PennDOT, this project presented challenging structural designs, traffic analysis and complex geometry and roadway designs. The designs were further complicated because of the high volume of traffic on Interstate 79, SR 22/30 and the parkway. The design process took approximately four years and cost more than $8 million.

PennDOT also faced right of way (ROW) challenges due to the abandoned coal mines on the project site. Permits for ROW and processing cost approximately $3 million. As part of environmental mitigation, the abandoned coal mines were sealed off.

M.A. Beech Corporation of Carnegie Borough, Pa., was contracted for construction inspection because of the size of the project. Don Stape, inspection manager, said that his role was to make sure that everything on the job was in compliance with PennDOT specifications.

Stape described the latest anti-icing technology used on the parkway ramps.

“The design incorporated an automated anti-icing system in the decks of each bridge. The pump house and storage tank is located 300 feet from the bridges. The chemicals are piped up piers into parapets and through the bridge decks.”

Stape said that this technology is very current and superior to previous applications.

There are 32 subcontractors assigned to the Parkway West project. Suppliers include High Steel Structures of Lancaster, Pa., for steel beam fabrication; Newcrete Products of Roaring Spring, Pa., for concrete beam fabrication; and Penn Line Services of Scottdale, Pa., for guide rails. Two companies supplied concrete: Arrow Concrete Company of Pittsburgh and Wine Concrete Products of Sewickley, Pa.

The electrical and integrated transportation system was handled by Bruce & Merrilees Electric Company of New Castle, Pa. All Crane Rental of Pennsylvania provided the cranes. The ROW fencing was installed by Interstate Fence Supply of Altoona, Pa. John Gulisek Construction Company of Mount Pleasant, Pa., is providing the concrete paving service.

The crews employed a number of machines on the job, including bulldozers, track loaders, excavators, scrapers, cranes, drill rigs and articulated trucks. Many were Caterpillar, which included a Cat D11 dozer with ripper, which was used for the main cut excavation, and a D11.

For crane work, crews used a Link-Belt LS218 truck-mounted crane and a Link-Belt LS138. For steel and concrete beam erection, they used a Grove 300TN and a Grove 500TN, respectively.

The ribbon-cutting ceremony for the two ramps took place on Dec. 9, 2008. PennDOT expects to have the entire project complete by May 2009. CEG