Adhesion Coefficient
Reference values of the adhesion coefficient α are listed in the following table:
Empirical adhesion coefficient α
Pile material | Soil consistency | Cohesion range cu [kPa] | Adhesion coefficient α [-] |
Timber and concrete piles | Very soft | 0 - 12 | 0.00 - 1.00 |
Soft | 12 - 24 | 1.00 - 0.96 | |
Medium stiff | 24 - 48 | 0.96 - 0.75 | |
Stiff | 48 - 96 | 0.75 - 0.48 | |
Very stiff | 96 - 192 | 0.48 - 0.33 | |
Steel piles | Very soft | 0 - 12 | 0.00 - 1.00 |
Soft | 12 - 24 | 1.00 - 0.92 | |
Medium stiff | 24 - 48 | 0.92 - 0.70 | |
Stiff | 48 - 96 | 0.70 - 0.36 | |
Very stiff | 96 - 192 | 0.36 - 0.19 |
Literature:
NAVFAC DM 7.2, Foundation and Earth Structures, U.S. Department of the Navy, 1984.