A Maryland State Highway Administration (SHA) project currently under way in Bladensburg, Md., involves the construction of a railroad grade-separation crossing over MD 450 and the improvement of an intersection near the Pease Cross.
The total cost of the project is $70 million, with funding coming from a combination of CSX, federal and state funds. The contractor is Balfour Beatty Infrastructure Inc., and the project director is Greg McVey.
It has been ongoing since the fall of 2004, and is anticipated to be complete by late summer 2009, if the weather permits. In January, it was 80 percent complete and on target for the completion date.
“More than 52,000 vehicles travel along MD 450 in Bladensburg daily. By 2025, traffic is expected to exceed 85,000 vehicles. Before the project began, the CSX tracks were located at street level and crossed MD 450,” said Kimberly Frum, SHA’s district community liaison for district 3. “With tracks at street level and trains crossing MD 450 more than 25 times a day, traffic stopped repeatedly, creating congestion and delaying the response of emergency crews. The backups created by the trains were known to cause delays of up to a mile or more. The bridge eliminated the traffic bottleneck caused by the trains, and enhanced motorist and pedestrian safety.”
The proposed bridges will consist of separated grade crossings of CSX at MD 450 and at Upshur Street. In addition, a bridge will be constructed over the tributary to the Anacostia River located north of Upshur Street.
Frum noted that a temporary track was constructed 20 in. (51 cm) west of the existing track in order to construct the proposed retained fill sections and bridge structures. The permanent track will be constructed 15 in. (38 cm) east of the existing track.
The steel for the bridge was set in place in April 2008, requiring a complete closure of MD 450 for a weekend.
“During the closure, two 120-ton steel beams were set in place directly over the travel lanes of MD 450,” Frum said. “In addition, three cranes were needed to lift the beams and they were staged on the lanes of MD 450, necessitating the total road closures. There were additional weekly overnight lane closures to set the remaining cross beams in place.”
The original street level tracks were removed in January, and crews repaved the track-free roadway at that time.
Frum reported that one of the challenges for this particular job involved building a temporary track to allow for the permanent retained fill structure to be built.
“This meant installing permanent sheet pile 750-feet long to support fill material for the temporary track,” she said. “In addition to the permanent sheet pile, temporary sheet pile was installed along the length of the proposed structures for support of excavation.”
Following the switch to the temporary track, the contractor began installing DeWaal piles for the footings of the structures.
“DeWaal piles are a type of soil displacement piles that produce little to no spoils as compared to auger cast piles,” Frum explained. “This was the first project on which the State of Maryland has used this type of pile. The contractor could have used standard H-piles, but due to the close proximity of existing buildings and the Historic New Hope Baptist Church, there was concern of excessive vibrations during pile installation. The contractor was also required to monitor vibrations during construction activities within close proximity to the existing buildings.”
When the pile installation started, the prime contractor began excavating for the footers. However, it was soon determined that hazardous waste was present in the soils throughout the project limits. This required that the excavated material be hauled to a licensed disposal facility, where it was treated.
“Once the footers were constructed, the contractor began building the retaining walls for the structures,” Frum said. “Coordination was of the utmost importance due to working next to live rail traffic. A CSX flagman is on site daily to coordinate with the contractor.”
Additional sheet pile was installed using a Delmag RH32W for support of excavation next to an existing building.
“Unlike a vibratory or impact hammer, these piles were installed using a push-pull action,” Frum said. “This method limited vibrations that could adversely affect the existing structures.”
During all the construction activities, SHA and the contractor worked together to minimize interference to adjacent businesses. Due to the volume of traffic, providing traffic maintenance is also of utmost concern to ensure safety to both pedestrians and motorists.
“This project is unique because it is an above-grade fill structure that will handle two active rail lines,” Frum explained. “The limited construction area to build this structure is also special due to the surrounding building. Finally, the sheer volume of concrete and rebar used to complete the structures and bridges far exceeds many SHA projects.”
In addition, the job is required to adhere to AREMA railroad and SHA specifications during both the design and the construction phases.
Cranes of various sizes are being used on the job, including up to 500 tons (453 t) for setting the exterior girders over MD 450 and Upshur Street. In addition, major equipment used includes pile driving equipment, a vibratory hammer, a Delmag RH32W, and a Giker crush piler.
The total length of the project is 1.1 mi. (1.7 km). In January, approximately 1,200 cu. yds. (917 cu m) of concrete had been used in the footing at the bridge structures. In addition, 32,000 cu. yds. (24,466 cu m) of concrete was used in retaining walls and wing walls, including footings, and 1,700 cu. yds. (1,300 cu m) was used in substructure. A total of 3,678 piles had been installed for the footings of the retaining walls and bridges.
Major subcontractors include Bardon Inc. (Aggregate Industries – Mid Atlantic), Greenbelt, Md., which supplied concrete, aggregate, and asphalt; Balfour Beatty Rail, Eighty Four, Pa., which installed CSX rails; Giken America Corporation, Orlando, Fla., which installed temporary and permanent sheet pile; High Steel Structures, Lancaster, Pa., which installed structural steel for the three bridges; Morris Shea Bridge Company Inc., Irondale, Ala., which installed the DeWaal pile system for the retaining wall and bridge structures; National Cable Construction, Sterling, Va., which dealt with any test pits and relocations of AboveNet (fiber optic) communication line; Prince Construction Company Inc., Washington, D.C., which installed reinforcing steel bars for all retaining walls and abutments; and Schnabel Engineering North LLC, Baltimore, Md., which performed vibration monitoring during sheet pile, H-pile, and DeWaal pile operations. CEG
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