First phase of Metro Silver Line extension near completion - Boston News, Weather, Sports | FOX 25 | MyFoxBoston

First phase of Metro Silver Line extension near completion

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McLEAN, Va. -

After five years and nearly $3 billion, the first phase of the new Silver Line Metrorail extension is almost complete. Testing is underway on the tracks and workers are putting the finishing touches on the five stations.

"We're about 97 percent complete on all the stations," said Marcia McAllister, a spokesperson with the Dulles Corridor Metrorail Project.

The project is over budget and behind schedule. The 2008 contract called for the 11.7 mile project to cost $2.6 billion, but that was later raised to $2.95 billion. It is now expected to be complete in the next two months.

McAllister and a team with the Metropolitan Washington Airports Authority and Dulles Transit Partners, which is building the rail line, showed us the progress at the McLean station at Tysons Corner.

Wires protrude from the ground where the fare gates will be placed. There is lighting still to be installed and signs put in place, but the bulk of the work is done.

"We're still on track for November," McAllister said. "But we don't have a specific date yet."

Amid the sounds of equipment beeping and power saws cutting, the station's design stands out. The steel construction and skylights give the Silver Line Metro stations a modern look.

"It's a very different architecture," said Stephen Barnam, the senior product manager for construction. "They were going for an open look, try to have as much light as possible…and feel like a comfortable place."

The walkway over the road is enclosed -- not with glass -- but a steel mesh to keep air flowing. The floor is pressed concrete instead of the tiles used in Metro's other stations.

The first phase adds five new stations between Tysons Corner and Reston. The rail line, which towers above the road, is hard to miss. It is five stories high at its peak.

"It's amazing to us we built six miles of aerial guideway, through Tysons Corner and a tunnel, two tunnels," McAllister marveled.

The tunnels run beneath Chain Bridge Road and International Drive.

It took 186,927 cubic yards of concrete and 1,638 tons of steel to build the project. That is enough concrete to build three football stadiums and enough steel for 1,365 cars.

The construction caused countless road closures and detours over the course of the project, in an area already known for traffic congestion.

There were setbacks too. Changes had to be made to comply with National Transportation Safety Board recommendations following the deadly 2009 Red Line train crash and workers ran into problems moving the utilities.

"It was about a year and a half of preparatory work before the rail line started just moving utilities," said Barna.

Testing is underway, and rail cars are running on the new sections of track, but it will not be ready to open until next year.

"The test trains that are running are full of test equipment and that's what they do. They're not the kind of train cars that you'll be riding," said McAllister.

Once construction is complete in November and it is operationally ready, the new rail line will be turned over to Metro for acceptance. The transit agency will then need up to another 90 days to do additional testing and train workers.

The stations will be equipped with all the latest technology for signs and kiosks, but it is the basics that some people might find helpful. Commuters on the go, who need to go, will be happy to know these stations, unlike many others in the Metro system, do have public restrooms.

As for the escalators and elevators, which are notorious for breaking down in the Metro system, Barnam gave his pledge, "I can promise you they will work."

One downside: only two of the stations will have parking. Wiehle Ave-Reston East at the end of the line will have a public parking garage with more than 3,000 spaces built by Fairfax County. A private company is expected to provide a temporarily lot with about 700 spaces at the McLean station.

The Silver Line is ready and on track to open in the coming months. Work on Phase 2 of the Silver Line, which runs to Dulles International Airport, is underway but will not be complete for another five years.

LINKS:

Link to video of the Wiehle-Reston East pedestrian walkway being installed: http://www.bechtel.com/4634.html

Link to Dulles Corridor Metrorail Project website: http://www.dullesmetro.com/index.html

Basic construction facts (Source: Dulles Transit Partners/Dulles Corridor Metrorail Project)

FACTS

GENERAL:

Design-Build Contractor: Dulles Transit Partners, LLC

(Bechtel and URS)

Stations: 5

Total Length of Alignment: 11.7 miles

Total Track: 24,350 linear feet

Total Project Concrete: 186,927 cubic yards

Total Systems Conduit: 360,904 linear feet

Total Steel Used in Stations: 1,638 tons

ECONOMIC IMPACT:

DTP Employment

(peak staffing per category): Professional staff: 500 (April 2011)

Direct Hire Craft Workers: 1000 (April 2011)

Subcontractor Employees: 630 (June 2013)

AERIAL GUIDEWAY:

Total Length: 6 miles (3 miles inbound/3 miles outbound)

Total Support Piers: 214

Average Height of Guideway: 35.7 feet

Tallest point of the Guideway: 55 feet

(Located above the southbound entrance from Route 123 to I-495)

Total Segments Placed: 2,769

Segment Material: Pre-cast concrete

(Manufactured at a temporary plant at Dulles Airport, custom engineered to

fit a specific location along the alignment and "match-casted" to fit its

neighboring segments.

Segment Weight: From 25 to 40 tons each

Average Segments Per Span: 12

Total Aerial Spans: 258

Average Span Length: 120 feet

How they are connected: Post-tensioned cables

(Each cable is approximately six inches thick and made up of up to 19

strands of high strength twisted steel threaded through the segments in each

span anchored into steel blocks at the end of each span. Pulled tight (post

tensioned with approximately 4.5 million pounds of force (for an average

120 foot span)).

Total Length of Post Tensioned Cables: 39 miles

Total Length of High Strength

Steel Strands in Cables: 528 miles

Total Aerial Acoustical Barriers: 45,800 linear feet

Total Horizontal Trusses Used on Project: Three

Weight of Truss: 365 tons

Length of Truss: 360 feet

TUNNELS:

Tunnels: Two (one Inbound and one Outbound)

Location: Intersection of Chain Bridge Road and International Dr.

(Highest natural elevation in Fairfax County)

Length: 2,400 linear feet (approximately)

Tunneling Methods: 700 lf of Cut and Cover

1,700 lf of NATM (New Austrian Tunneling Method)

(Tunnels excavated and constructed in short sequential

portions)

Tunnel Depth: Between to 30 feet

Excavation: 100,000 cubic yards of earth

Equipment: Drill Jumbo with Pipe Arch Canopy System Tooling

Tunnel Excavators

Shotcrete Batch Plant

Shotcrete robots for application

Total Shotcrete sprayed for initial liner: 25,000 cy

Total Concrete placed for final liner: 18,000 cy


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