EN 1997-1:2024/prA1

EN 1997-1:2024/prA1 is a CEN draft amendment to Eurocode 7 - Geotechnical design - Part 1: General rules. It is submitted for enquiry and, if approved, will modify EN 1997-1:2024 for people who design, check, and verify geotechnical structures.

What does EN 1997-1:2024/prA1 specify?

EN 1997-1:2024/prA1 updates the general rules for the design and verification of geotechnical structures. The amendment is aimed at structures outside the scope of EN 1997-3, and it is intended to be used with EN 1990, EN 1997-2, EN 1997-3, and other Eurocodes.

The document is organized as a foreword and 10 modification clauses. Those clauses cover the whole document, the Introduction, normative references, terms and definitions, basis of design, material, ground water, ultimate limit state, implementation of design, and the bibliography.

What are the key requirements of EN 1997-1:2024/prA1?

EN 1997-1:2024/prA1 mainly revises cross-references, selected design figures and notes, and a few wording points that affect how the base standard is applied in practice. It does not rewrite the whole Eurocode, but it changes several places that designers and reviewers use directly.

Updated references and Eurocode links

• Clause 1 and Clause 2 replace older references to EN 1990, EN 1997-2 and EN 1997-3 with updated part-numbered versions. In practice, users need to follow the newer companion standards when applying this part.
• The Introduction adds EN 19100 Eurocode 10 - Design of glass structures to the list of Eurocodes. This matters because the family of Eurocodes listed here is being extended.
• Clause 2 also updates the reference to EN 1991-1-1:2025. That keeps the document aligned with the current load and action reference set.

Basis of design and national choices

• Clause 4 updates the wording of Tables 4.1, 4.2 and 4.3 from “Lower” and “Higher” to “Low” and “High”. This is a wording change, but it matters because these tables support national choices and must be read consistently.
• Clause 4.1.3(1) revises the note on geotechnical structures whose integrity is vital for civil protection. The examples include earth dams connected to aqueducts and energy plants, earth dams and tailing dams with extreme consequences upon failure, and foundations of nuclear structures.
• The changes in Clause 3 remove several symbols and definitions from 3.2.1, so design documents and calculations should follow the revised notation.

Ground water, ultimate limit state, and execution

• Clause 6 changes the key for Figure 6.1 by deleting “(annual maximum)” from X2. That affects how groundwater-related input is interpreted in design work.
• Clause 8 revises Figures 8.1 and 8.2 and their notes. The new Figure 8.2 key identifies upward groundwater flow, water pressure with depth, and vertical effective pressure with depth, which is relevant for seepage, uplift, and stability checks.
• Clause 8 also adds “pore” before “water” in the note on dilatancy and excess porewater pressure. That is a clearer reminder that porewater effects are part of the failure analysis.
• Clause 10 tightens two execution-related statements: the probability of human errors during execution is to be minimized, and monitored changes in behaviour are to be checked against construction activities. In practice, this links design assumptions to site control and monitoring.

What terms does EN 1997-1:2024/prA1 define?

EN 1997-1:2024/prA1 uses the Eurocode terms for geotechnical structures, meaning structures whose design depends on ground and groundwater conditions.

It uses ground investigations for the planned, executed, and interpreted investigations that provide design data. The document ties these investigations to qualified people, because the quality of the design depends on the quality of the ground data.

It uses ground water in the design sense of groundwater conditions and pressures, including upward flow and porewater pressure effects. These are important because they can change stability and effective stress.

It refers to ultimate limit state, the design situation where failure mechanisms are checked. Clause 8 updates the figures and notes used for those checks.

It refers to National Annexes as the place where Member States set values related to regulatory safety matters. That is important because some design choices are nationally determined.

Who uses EN 1997-1:2024/prA1?

EN 1997-1:2024/prA1 is used by geotechnical engineers, structural engineers, and designers who work on foundations, earthworks, excavations, and underground works. It is also relevant to people who plan and interpret ground investigations, because the design rules rely on qualified collection and evaluation of ground data.

Quality managers, checking engineers, and site teams use it when they need to verify execution, compare monitoring results with construction activities, or review whether the design assumptions still hold on site. The examples in the document also point to use in earth dams, tailing dams, and nuclear-related foundation work.

What changed in EN 1997-1:2024/prA1 from the previous edition?

EN 1997-1:2024/prA1 is a draft amendment that will modify EN 1997-1:2024. The stated changes include updated references throughout the document, addition of EN 19100 in the Introduction, revised normative references, deletion of several symbols and definitions in Clause 3, wording changes in Clause 4 tables, updated groundwater and ultimate limit state figures, and revised execution wording in Clause 10. The bibliography also updates the reference to EN 1990-2.

Which standards are used with EN 1997-1:2024/prA1?

EN 1997-1:2024/prA1 is intended to be used with EN 1990-1:2023+A1:2026, which provides the basis of structural and geotechnical design for new structures. It is also used with EN 1997-2:2024+A1:2026 for determining ground properties from ground investigations, and with EN 1997-3:2025+A1:2026 for specific rules for certain geotechnical structures.

The amendment also refers to EN 1991-1-1:2025 and EN 19100 Eurocode 10. In practice, these references tell users which companion documents they need to consult when actions, glass structures, or other Eurocode topics are part of the project.

What does the EN 1997-1:2024/prA1 document contain?

EN 1997-1:2024/prA1 contains amendment instructions rather than a full rewritten standard. The main technical material is in revised text for Clauses 1, 2, 3, 4, 5, 6, 8, 10, and the bibliography.

It updates Tables 4.1, 4.2 and 4.3, and Figures 6.1, 8.1 and 8.2. It also changes notes, symbols, and a few terms so that the consolidated publication matches the updated Eurocode references and design checks.