Correlation Coefficients for Evaluating of Bearing Capacity of Piles from CPTs
Correlation coefficients ξ for evaluating of bearing capacity from CPTs (n - number of CPTs)
ξ for n = | 1 | 2 | 3 | 4 | 5 | 7 | 10 |
ξ3 | 1.40 | 1.35 | 1.33 | 1.31 | 1.29 | 1.27 | 1.25 |
ξ4 | 1.40 | 1.27 | 1.23 | 1.20 | 1.15 | 1.12 | 1.08 |
For the NBN EN 1997-1 ABN standard, the correlation coefficients are defined according to the density of CPTs on the construction site.
The coefficient ξ3 is taken as follows:
NUMBER OF PILES | CPT DENSITY | ||||
1 CPT per 10 m2 | 1 CPT per 50 m2 | 1 CPT per 100 m2 | 1 CPT per 300 m2 | 1 CPT per 1000 m2 | |
1-3 | 1,25 | 1,29 | 1,32 | 1,36 | 1,40 |
4-10 | 1,15 | 1,19 | 1,21 | 1,25 | 1,29 |
> 10 | 1,14 | 1,17 | 1,20 | 1,24 | 1,27 |
The coefficient ξ4 is taken as follows:
NUMBER OF PILES | CPT DENSITY | ||||
1 CPT per 10 m2 | 1 CPT per 50 m2 | 1 CPT per 100 m2 | 1 CPT per 300 m2 | 1 CPT per 1000 m2 | |
1-3 | 1,08 | 1,17 | 1,23 | 1,31 | 1,40 |
4-10 | 1,00 | 1,07 | 1,13 | 1,21 | 1,29 |
> 10 | 1,00 | 1,06 | 1,12 | 1,20 | 1,27 |