September 1, 2014

12 hours, 220 trucks, 3500 tons of concrete, 450 tons of steel

If there is any doubt that there is potential power in wind, take a look at the materials it takes to withstand its force.

In a 12-hour process over the past weekend, Clemson University’s wind turbine testing site poured the concrete foundation for its 15-megawatt test rig.  Engineers poured 3,500 tons of concrete poured into the foundation base — enough concrete to pave more than a half-mile of a two-lane interstate.

courtesy of Clemson University, Peter Hull

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. Image: Peter Hull

“We had more than 220 concrete trucks that needed to be unloaded and they had to get here from two different concrete plants via a combination of I-26 and local roads. The concrete has to be poured on a tight timetable so that the concrete does not set up too soon,” said Jim Tuten, the project manager of the Restoration Institute’s Wind Turbine Drive Train Testing Facility.

He said 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.

The foundation must be sturdy enough to handle multiple windmill blades, each of them being hundreds of feet long.

“If you can imagine the wind pushing on a set of blades that are 500 feet in diameter, almost the size of a football field, the forces are so great that we have to support it with something and that’s what this foundation does,” said Tuten.

Scientists will use hydraulics to replicate the force of the wind for the large-scale turbines which will be sent all over the world.

“The pre-planning for this took about four months, just the logistics,” said Tuten. “Not only did we have to get the concrete here, we had to perform quality tests on the concrete as it was coming on site, as it was being poured.”

With a $45 U.S. Department of Energy grant and $53 million of matching funds, Clemson broke ground in 2010 on the redevelopment of an 82,000-square-foot warehouse on the former Charleston Navy base.

The project is on budget and somewhat behind schedule because of the level of advanced engineering the building requires, according to Tuten. 

When complete later this year, the facility will have the capability for 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.

Clemson will soon announce another testing expansion to the facility. This addition is fully-funded, mainly with private money.