Sectional Monopole Tower Foundation & Installation Manual, Revision A
9
Soil Conditions
As with the Wind Zones described above the size of a foundation required to support a wind turbine and tower is in part determined by the soil
conditions in which the foundation is constructed. Loose sandy soil will require a larger foundation than bedrock.
Refer to the following tables to determine your Soil Class and the location of the foundation dimensions for your tower height and foundation type.
Soil Class
Description
1
Crystalline Bedrock
2
Sedimentary and Floated Rock
3
Sandy Gravel and / or Gravel
4
Sand, Silty Sand, Clayey Sand, Silty Gravel, and Clayey Gravel
(SW, SP, SM, SC, GM, and GC)
5
Clay, Sandy Clay, Silty Clay, Clayey Silt, Silt and Sandy Silt
(CL, ML, MH, and CH)
Tower Height
Foundation
Wind Zone
For Dimensions See
33.5 ft (10.2 m)
Mat
5 **
Appendix A, Sheet S-4A
33.5 ft (10.2 m)
Pier
1,2,3,4,5
Appendix A, Sheet S-4B
33.5 ft (10.2 m)
SMarT
5 **
Appendix A, Sheet S-4C
45 ft (13.7 m)
Pier & Pad
1,2,3,4,5
Appendix B, Sheet S-5 & S-7
45 ft (13.7 m)
Pier
1,2,3,4,5
Appendix B, Sheet S-5 & S-7
45 ft (13.7 m)
SMarT
5 **
Appendix B, Sheet S-5 & S-7
** Note the foundation dimensions and construction details for the SMarT and Mat foundations do not vary as a result of the soil conditions. These
foundations assume Soil Class 5 (worst case) conditions exist and are designed accordingly.
