Page 212 - Fluid Power Engineering

184 Chapter Nine

Threaded bolts
on a template Inner form CMP

Soil backfilled in
inner CMP

Concrete pour between Outer form CMP
inner & outer CMP

FIGURE 9-14 P&H Pier foundation for a Vestas 660-kW in 1999 at a site in
Nebraska. (With permission from Patrick and Henderson, Inc.)

for a Siemens 2.3-MW IEC IA turbine with 101-m rotor and 80-m hub
height are seen in Table 9-3. The construction process of a P&H ten-
sionless foundation consists of:

Excavate foundation hole that is at least 24 in. larger than the

outer corrugated metal pipe (CMP) diameter.
A CMP is placed in the hole to provide a mold for casting

concrete.
Sand and cement slurry is put to backfill the area between the

soil and outside surface of the CMP.
An embedment ring is placed at the bottom of the CMP. A

template ring is placed at the top of the CMP. Holes in the
embedment ring and template match the bolt pattern in the

Parameters Dimension
Outer CMP diameter 16 ft
Inner CMP diameter 12 ft
Height of foundation 34 ft
Number of anchor bolts 160 (80 in each ring)
Outside diameter of anchor bolt 1.5-inch ASTM A-615

Source: With permission from Patrick and Henderson, Inc.
TABLE 9-3 Approximate Dimensions for P&H Tensionless Foundation
for Siemens 2.3-MW IEC IA