Page 355 - Fluid Power Engineering

Planning and Execution of W ind Projects 315

the constructed areas are graded and areas disturbed because of con-
struction are restored to the original state by reseeding with native
vegetation.
Foundation Construction and Turbine Erection
Foundation Construction
The foundation design provides the specifications and instructions
for foundation construction. From a project-planning perspective, the
generic steps are:
Hundreds of cubic meters of soil is excavated or drilled and

blasted, depending on the type of soil.
An outer form is placed, followed by rebar, and then by a bolt

cage assembly along with conduits for cables and lightning
protection.
Concrete is then poured and cured. Curing time may be as

much as 1 month, depending on the size of the foundation.
The outer form is then removed and the area around the foun-

dation is backfilled and compacted.
In the middle of the foundation is an embed ring with bolts

sticking out. The tower is bolted to this embed ring.
A picture of partially complete foundation is in Fig. 14-4.

FIGURE 14-4 Spread foundation after concrete has been poured in the footing
of the foundation. (Courtesy Vensys Energy AG.)