Talk about a firm foundation! The wind turbines at MWCC literally will be anchored to the earth through extraordinary engineering that requires one-third less concrete and other materials than a traditional gravity foundation.
“We’re basically nailing them to the ground,” explained Lloyd Purdy, an engineering technician with EarthSystems Global, Inc., who is on site this week for the foundation work. The California-based company works with Patrick and Henderson, Inc. in providing engineering design support for wind projects.
MWCC’s turbines are being installed with P&H rock/pile anchor foundations. Last week, crews from Emerald Excavation of Plymouth (a WBE – Women Business Enterprise) excavated the two foundation holes. That’s the same company that built the access road and completed the duct bank trenching this summer. Once the holes were excavated, Boart Longyear, a global company based in Utah with a Massachusetts branch in North Reading, drilled 45 to 65 feet into soil and bedrock to install 18 anchors per foundation.
This week, reinforcing steel, called re-bar, was installed in the north turbine foundation to increase the strength of the concrete. Today, crews from S&F Concrete of Hudson filled the foundation structure with 85 yards of a specialty concrete that reaches a higher strength faster than ordinary concrete. Testing agents from Geotechnical Consultants, Inc. of Marlboro and Miller Engineering & Testing of Northboro are providing quality assurance/quality control while the foundation work ensues.
Next week, the process will be repeated when the foundation is built for the south turbine.
“It’s an awesome milestone,” remarked Ted Fiffi, resident engineer with the Massachusetts Division of Capital Asset Management.