Managing risk and achieving reliable geotechnical designs using Eurocode 7 - Risk and Reliability in Geotechnical Engineering - page 422

Table 10.12 Partial factor values in Austrian NA to Eurocode 7 for different Consequences Classes,
and Design Situ ations
Soil parameter

Symbol Partial material factor values γ M for different Consequences Classes

CC 1 CC 2 CC 3

Design Situations (BS)

BS 1 BS 2 BS 3 BS 1 BS 2 BS 3 BS 1 BS 2 BS 3

Effective angle of friction 1.10 1.05 1.00 1.15 1.10 1.05 1.30 1.20 1.10

γ tan ϕ '

Effective cohesion 1.10 1.05 1.00 1.15 1.10 1.05 1.30 1.20 1.10

γ c '

Undrained shear strength 1.20 1.15 1.10 1.25 1.20 1.15 1.40 1.30 1.20

γ cu

Uniaxial compressive
strength

1.20 1.15 1.10 1.25 1.20 1.15 1.40 1.30 1.20

γ qu

Weight density 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00

γ γ '

Table 10.13 Partial action factor values in German NA to Eurocode 7 for different Design Situations
Action Symbol Partial action factor values γ F for different Design Situations

BS-P (persistent) BS-T (transient) BS-A (accidental)

Unfavorable permanent action
Favorable permanent action
Unfavorable permanent earth pressure
Unfavorable variable action
Favorable variable action

1.35
1.00
1.20
1.50
0

1.20
1.00
1.10
1.30
0

1.00
1.00
1.00
1.10
0

γ γ G, inf
γ G, EO
γ γ Q

Table 10.14 Linkage of Geotechnical Categories to Consequences Classes, site conditions, and basis for
geotechnical design in France
Geotechnical Category Consequences Class Site conditions Basis for design

GC1 CC1 Simple and known Experience and qualitative investigations

GC2 CC1 Complex Site investigations and design

CC2 Simple or complex

GC3 GC3 Simple or complex Site investigations and detailed design

the level and quality of the geotechnical investigations and design calculations, as shown in
Table 10.14 from Orr (2013). This method of reliability differentiation is based on the qual-
ity management differentiation outlined in EN l990, with three Design Supervision Levels,
DSL1, DSL2, and DSL3, and three Inspection Levels during construction, IL1, IL2, and
IL3, that may be related to the three Reliability Classes, as shown in Table 10.15 , or chosen
according to the importance of the structure and in accordance with national requirements.
These are also linked in Table 10.15 with the minimum requirements in Eurocode 7 for the
different Geotechnical Categories. The Design Supervision Levels are implemented through
the adoption of appropriate quality management measures.

10.6 ConCluSIonS

Eurocode 7 provides a broad framework to identify the complexity of geotechnical
design situations and to manage and reduce the risks in geotechnical design to acceptable