# A.3.3.3 Correlation factors for pile foundations

(1) P For verifications of structural (STR) and geotechnical (GEO) limit states, the following correlation factors ξ shall be applied to derive the characteristic resistance of axially loaded piles:

- ξ
_{1}on the mean values of the measured resistances in static load tests; - ξ
_{2}on the minimum value of the measured resistances in static load tests; - ξ
_{3}on the mean values of the calculated resistances from ground test results; - ξ
_{4}on the minimum value of the calculated resistances from ground test results; - ξ
_{5}on the mean values of the measured resistances in dynamic load tests; - ξ
_{6}on the minimum value of the measured resistances in dynamic load tests.

NOTE The values to be ascribed to ξ_{1}, ξ_{2}, ξ_{3}, ξ_{4}, ξ_{5} and ξ_{6} for use in a country may be found in its National annex to this standard. The recommended values are given in table A.9, in table A.10 and in table A.11.

*n*– number of tested piles)

ξ for n = |
1 | 2 | 3 | 4 | ≥ 5 |

ξ_{1} |
1,40 | 1,30 | 1,20 | 1,10 | 1,00 |

ξ_{2} |
1,40 | 1,20 | 1,05 | 1,00 | 1,00 |

*n*– the number of profiles of tests)

ξ for n = |
1 | 2 | 3 | 4 | 5 | 7 | 10 |

ξ_{3} |
1,40 | 1,35 | 1,33 | 1,31 | 1,29 | 1,27 | 1,25 |

ξ_{4} |
1,40 | 1,27 | 1,23 | 1,20 | 1,15 | 1,12 | 1,08 |

^{a, b, c, d, e}(

*n*– number of tested piles)

ξ for n = |
≥ 2 | ≥ 5 | ≥ 10 | ≥ 15 | ≥ 20 |

ξ_{5} |
1,60 | 1,50 | 1,45 | 1,42 | 1,40 |

ξ_{6} |
1,50 | 1,35 | 1,30 | 1,25 | 1,25 |

^{a} The ξ-values in the table are valid for dynamic impact tests.^{b} The ξ-values may be multiplied with a model factor of 0,85 when using dynamic impact tests with signal matching.^{c} The ξ-values should be multiplied with a model factor of 1,10 when using a pile driving formula with measurement of the quasi-elastic pile head displacement during the impact.^{d} The ξ-values shall be multiplied with a model factor of 1,20 when using a pile driving formula without measurement of the quasi-elastic pile head displacement during the impact.^{e} If different piles exist in the foundation, groups of similar piles should be considered separately when selecting the number n of test piles. |

A.3.3.4 Partial resistance factors for pre-stressed anchorages

(1)P For pre-stressed anchorages and verifications of structural (STR) and geotechnical (GEO) limit states, set *R1*, *R2*, *R3* or *R4* of the following partial factors on resistance (γ_{R}) shall be applied:

- γ
_{a;t}on temporary anchorages; - γ
_{a;p}on permanent anchorages.

NOTE The values to be ascribed to γ_{a;t} and γ_{a;p} for use in a country may be found in its National annex to this standard. The recommended values for the four sets *R1*, *R2*, *R3* and *R4* are given in table A.12.

_{R}) for pre-stressed anchorages

Resistance | Symbol | Set | |||

R1 |
R2 |
R3 |
R4 |
||

Temporary | γ_{a;t} |
1,1 | 1,1 | 1,0 | 1,1 |

Permanent | γ_{a;p} |
1,1 | 1,1 | 1,0 | 1,1 |