670 and 680 Maine, The Wharf Parcels 6 & 7

Situated along Washington DC’s Southwest Waterfront, the Wharf Parcels 6&7 also known as 670 Maine and 680 Maine, consist of two 11-story, Class “A” office buildings (480,000 sf), which are part of the phase two development at the Wharf DC.  The office buildings consist of concrete framing with a post-tensioned concrete slab over a two-level underground garage extending under multiple towers.  

The hybrid foundation system is comprised of multiple foundation solutions, spanning over the Washington Metropolitan Area Transit Authority’s (WMATA) green line metro tunnel.  The transfer mat over the tunnel with rigid anchor and drilled displacement piles create an innovative solution to control the settlement.  Also, vibration isolation was included to eliminate any vibration and noise for the tenants. 

To create a maximum unobstructed interior space within the buildings, columns were spaced up to 42 feet and 15 feet cantilevered slabs all around the perimeter of floor plates guaranteed open and continuous views through the sophisticated curtainwall and glazing system.  An innovative shallow 81 feet concrete post-tensioned bridge connecting the two buildings with an oculus in the middle created a dramatic view while the interior open space with the bridge was used as the continuation of the office space.