In August 2004, the Virginia Department of Transportation (VDOT) and Archer Western Contractors began a three-year, $32-million project to replace and widen the I-64 eastbound and westbound bridges over the Acca Railroad Yard just west of the I-64/I-95 interchange in Richmond. Constructed in 1967, the original bridges featured four westbound lanes plus an exit for Staples Mill Road, and three eastbound lanes. However, after 40 years, the bridge substructures and decks had deteriorated, and there was damage to the back wall abutments. Furthermore, with studies indicating that traffic would increase from a current 151,000 vehicles a day to 211,400 by 2025, new, wider bridges had become necessary.
Prior to bid letting VDOT worked extensively with Joe Hardee, design project manager with URS Corporation, to ensure "a reasonable set of bid documents," according to Chris Winstead, VDOT Richmond District construction manager. "We sat down and came up with a constructability review of the plan as well as what we thought was a reasonable schedule for the contract performance period. We came up with a milestone; we came up with a completion date. We took a look at the various phases and tried to come up with a set of bid documents that was fair to the contracting industry, but also minimized impact on the traveling public."
With detailed plans in place, Archer Western Contractors won the bid and, according to Winstead, "elected to embrace the fairly intense critical-path schedule specification on the project, rather than looking at ways to get out of that special provision."
Using Primavera scheduling software, Jeff Will and Herb Dowling, project managers with Archer Western, worked closely with VDOT, URS and their subcontractors to properly resource the job.
"They executed the plan," says Winstead. "We had weekly partnering meetings and established a partnering charter. We talked in terms of our priorities: safety, quality, budget, and schedule. We wanted to stick to that charter."
CSX, which owns the Acca Railroad Yard, was also an active partner on the project.
"They solved problems with us," says Winstead. "We were building this bridge rehab right in their backyard. Acca yard is a very important terminal, and they were open with us about their concerns and needs. We were able to help them out as well and be good neighbors. There's no way we could have gotten to this point on the project without CSX's cooperation."
With the players and the game plan established, preliminary work on the three-phase project began in September 2004. All three phases were designed to minimize impact on traffic and three lanes in each direction were maintained throughout each phase.
Phase 1 began with repaving the approaches to the bridge and striping the lanes to 11-foot widths.
"Part of the design itself was to come in and place the asphalt overlay up front," says Mike Schwartz, VDOT transportation construction project engineer. "This minimized some of the traffic impacts at a later date."
On two separate weekends, the project team worked with a lane closure and traffic switches from Friday evening through Sunday evening, completing one lane in September and one lane in October. "By paving first, we could move traffic into 11-foot lanes and maintain those — three in the eastbound direction, four in the westbound direction — which gave us the opportunity to build the outside," adds Schwartz.
With the approaches finished, work began on rebuilding and widening the outside of the bridges. Each bridge required completely new abutments, new footer sections, drilled shafts and caissons for the extension to the existing piers, and "railroad crash walls" at the base of the piers to protect them in the event of a collision with a train. Spalling concrete and cracks were also repaired on the existing piers, and all of the pier caps were retrofitted. Extensive coordination and flexibility were necessary as work proceeded in the rail yard.
"It was tricky for the caisson contractor, Gemini, to work in-between the railroad trains and tracks," says Ray Johnston, P.E., VDOT project manager. "He would go out to start work, and when a train came he had to move his operations off of the train tracks to allow the train to come through. The trains have the priority, and we could have 85 known trains come through in a 24-hour period. We also had to wait for (railroad) crews to switch. It took awhile to get an understanding about what we wanted to do and how they worked, but once the flow and routine got going it went really well."
Phase 2 began in January 2006 when work switched to the inside eastbound lanes of the bridge. With three limited-access highways — I-95, I-64 and I-195 — coming through the project site, traffic control became a challenge. Throughout the project, VDOT worked closely with the media and the public to keep commuters and travelers informed about traffic changes and detours.
Working between concrete barriers, demolition began on the existing eastbound bridge deck. To demolish the bridge, Archer Western used a concrete rope saw with diamond teeth to cut the bridge's barriers. Then a modified band saw cut through the entire deck, which was removed in slabs.
During nighttime operations, Archer Western used two Caterpillar D9 dozers equipped with booms and pipe layers to remove and replace the bridge's steel beams. Using a crane was not possible due to the railroad tracks and constant yard activity as well as the presence of overhead power lines. The dozers allowed Archer Western to work from the top down and ultimately saved time on the project.
Another challenge on the bridge was mounting the sound walls to the bridge structure.
While the ground-mounted sound walls near the residential areas were pretty typical, the structure-mounted sound walls were connected to the back side of the bridge parapet.
"There was a lot of design challenge because of the height of the walls (13 feet) and the wind loads you have to account for," says Johnston. In addition, because the sound walls were not mounted to the top of the parapet, which is more typical, connecting them to the back required more detail that was not accounted for in the design specs.
"The designer of the bridge accounted for the sound wall, but he didn't detail connections to the bridge. That was up to the contractor, so the sound wall was essentially design-build."
CSX also raised some concerns about the sound wall and securing the panels. "We had to assure them that something hitting the wall panels wouldn't result in the panels falling and hitting their trains or tracks," add Schwartz. "That was something we had to evaluate as we went through the process."
By October 2006, Phase 2 bridge work on the eastbound side of the project was completed and traffic was moved to its final configuration — one month ahead of schedule. Phase 3, which began in late 2006 and included the westbound deck replacement, is nearly finished, with only the asphalt paving to be completed. Traffic should be returned to its final configuration by June or July — well ahead of the original October 2007 completion date.