The method may have been a bit unusual, but the old Woodrow Wilson Bridge was recently detonated just the same. A contest known as the Toughest Bridge Commute was held to give one driver the ultimate payback — the opportunity to trigger the detonation charges and bring down approximately half a mile of elevated steel girders that supported the old bridge over Jones Point Park in Alexandria, Va.
The winner was Daniel Ruefly of Accokeek, Md. His entry was submitted by his daughter, Tiffanie. Ruefly was injured in an accident on the bridge in 1999.
The demolition is part of the Woodrow Wilson Bridge Project, which is the largest public works project in the mid-Atlantic region. Its purpose is to replace the current bridge and four interchanges adjacent to it.
The $2.4 billion project is currently on schedule and within budget; it is more than 60 percent complete. The first new span was dedicated in May.
It is sponsored by The Federal Highway Administration, Virginia Department of Transportation, Maryland Highway Administration, and the District Department of Transportation.
The detonation took place just after midnight on Aug. 28. The timing was planned for safety reasons, and the process included a 30-minute total closure of I-95 (the Capital Beltway’s Inner and Outer Loops), a 30-minute no-fly period for aircraft, a 30-minute closure of the area of the Potomac River from the Navigation Channel west to the Virginia shoreline, and a public stand-back perimeter of 500 ft. A 350-ft. clear zone also was enforced by Alexandria police officers.
The main contractor of the demolition was Virginia Approach Contractors (VAC), with Dennis Brown serving as project engineer.
The demolition and removal process for the old bridge began July 17 after all traffic was switched onto the first new bridge. The portion of the old bridge over Jones Point Park in Alexandria was demolished first, since it crossed the footprint of the second new bridge that is under construction. The foundations for four piers and the abutment of the second new bridge could not be built until the old bridge and abutment were out of the way.
The deck of the bridge was first removed by excavator-mounted hydraulic hammers, then crushed to be used on-site for pier backfill and general site grading. Once the steel beams were cut, the concrete pier columns were then chipped away by hoe rams.
Once the miscellaneous steel and the bridge deck were removed, Brown reported that the beams were prepped for blasting by VAC and Demtech, the blasting contractor based in Dubois, Wyo. Celtic Demolition of Washington, D.C., did the concrete demolition.
“We went in and used torches to prep the beams for the installation of the explosives, and then we installed the explosives, set up the time and date, and did the demolition,” he said. “After that, we went in and cleaned up the aftermath with a sheer attached to an excavator. We loaded the steel beams up on a flatbed and then hauled them up to recycling.”
David Tackoor, resident engineer of Potomac Crossing Consultants (PCC), noted that the concrete from the deck was crushed and recycled for use on-site.
A total of 2,612 tons (2,370 t) of steel was removed, and concrete totaled 6,500 cu. yds. (5,000 cu m). Brown noted that planning for the demolition took approximately six months, and most of the challenges involved the urban location in old town Alexandria.
“Most of them were logistic as far as where we were located — right in downtown Alexandria,” he said. “We had to deal with the public and all of the historic structures — noises, air quality problems, and things of that nature.”
Brown noted that the most difficult aspect of the job was coordination among all the local state and federal agencies.
“It’s a very in-depth organization that we’re kind of working with here as far as being in Virginia working on a Maryland project inside a National Parks property, and also an Alexandria city property,” he said. “Getting all of those people pacified to what we were trying to do and get all the questions answered was probably the toughest thing for me.”
Detonation of the drawbridge portion of the old bridge occurred in four detonations over a six-week period.
Significant portions of the demolished drawbridge and Maryland Approach, including concrete and steel components, are being barged to the Chesapeake Bay to create fish reef as part of Maryland’s Department of Natural Resources Fish Reef Creation Program. CEG