| Standard | Title | Reference Tools | Reference Table |
|---|---|---|---|
| EN 1997-1 | General rules | - | - |
| EN 1997-2 | Ground investigation and testing | - | - |
What this standard covers
EN 1997 (Eurocode 7 - Geotechnical design) covers the design of foundations, retaining structures and earthworks, and the ground investigation that a geotechnical design must be based on.
EN 1997-1 gives the general rules: geotechnical categories, the design approaches and partial factor sets, and the verification of spread foundations, pile foundations, retaining structures, slopes and anchors against bearing failure, sliding, overturning, uplift and excessive settlement. EN 1997-2 covers ground investigation and testing, including how laboratory and in-situ results are turned into characteristic values.
A distinctive feature is that partial factors may be applied to actions, to material properties or to resistances, in combinations described as Design Approaches. Which approach applies is a national choice set in the National Annex, so the same ground and the same structure can be verified differently in different countries.
What you will find in it
- Geotechnical categories
- Classification of a problem by its complexity and risk, which sets the level of investigation and verification required.
- Design approaches
- The alternative arrangements of partial factors on actions, material properties and resistances, selected by the National Annex.
- Characteristic values
- How a characteristic value of a soil parameter is selected as a cautious estimate, which is where most geotechnical judgement is exercised.
- Spread foundations
- Bearing resistance, sliding and settlement of pads, strips and rafts, in drained and undrained conditions.
- Pile foundations
- Compressive and tensile resistance of piles from ground parameters, from static load tests and from dynamic methods, and group behaviour.
- Retaining structures
- Earth pressures on gravity, embedded and composite walls, and verification against rotation, translation and overall stability.
- Slopes and overall stability
- Stability of natural and engineered slopes, including the effect of groundwater and of the structures founded near them.
When to use this standard
Use EN 1997 whenever the ground is part of the structural problem - a spread footing, a raft, a pile, a retaining wall, an anchor, a slope or an excavation. The concrete or steel of the foundation itself is designed to EN 1992 or EN 1993; EN 1997 determines what the ground can carry and how much it will move.
How it fits with the other standards
Ground investigation follows EN 1997-2. Actions on the structure come from EN 1991 and are combined by EN 1990; the foundation itself is then designed to EN 1992 or EN 1993, and seismic geotechnical design is covered by EN 1998-5. The Vietnamese equivalents are TCVN 9362 for shallow foundations and TCVN 10304 for piles.
What each part covers
- EN 1997-1
- The general rules: geotechnical categories, the Design Approaches and their partial factor sets, and the verification of spread and pile foundations, retaining structures, slopes and anchors.
- EN 1997-2
- Ground investigation and testing. The field and laboratory tests a geotechnical design must be based on, and how their results are turned into characteristic values of soil parameters.