NORTH CHARLESTON — Construction of Clemson University’s Wind Turbine Drivetrain Testing Facility at the Restoration Institute reached another milestone last Friday when the foundation for the larger test rig was poured.

Beginning late Friday, engineers with Choate Construction poured 1,900 cubic yards of concrete into a pit 50 feet wide by 100 feet long by 15 feet deep, all resting on 115 seventy foot-deep piles, to form the 15-megawatt test rig foundation.

If those piles were placed end-to-end, they would cover a distance of more than a mile-and-a-half. To put it another way, the building’s foundation is almost seven stories deep. The pit already has approximately 450 tons of reinforcing steel weighing roughly as much as 250 mid-size cars.

There was about 3,500 tons of concrete poured into the foundation base — enough concrete to pave more than a half-mile of a two-lane interstate or for the slabs of about 225 two-car garages.

Beginning late last Friday, engineers with Choate Construction poured 1,900 cubic yards of concrete into a pit 50 feet wide by 100 feet long by 15 feet deep to form the 15-megawatt test rig foundation. Photo credit: Peter Hull

The massive pour lasted through the night to take advantage of generally calmer weather conditions and minimize traffic congestion. The operation is expected to take up to about 12 hours.

Click here to view a streaming web cam of the testing facility construction site.

The operation has taken months of planning and thousands of man-hours of preparation and field work. Engineers must consider environmental conditions, influence from local traffic and other factors that could cause an inconsistent flow of concrete.

The pour marks a milestone for the massive construction project. After breaking ground in October 2010, construction began the following year. In May last year, the engineering team from Choate poured the foundation for the smaller test rig. The pour for the 7.5-megawatt test rig required 750 cubic yards of concrete.

The project involves completely redeveloping an 82,000-square-foot warehouse on the former Navy base. Engineering design was performed by AEC Engineering of Minneapolis.

In November 2009, Clemson and its partners were awarded a $45 million grant from the U.S. Department of Energy, which was combined with $53 million of matching funds, to build and operate the large-scale testing facility for next-generation wind turbine drivetrains.

When complete later this year, the facility will have the capability for full-scale highly accelerated testing of advanced drivetrain systems for wind turbines in the five- to 15-megawatt range.

It also will have 50 hertz and 60 hertz testing capability, which means it can accommodate test specimens destined for anywhere in the world.