Foreword

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This document was prepared by Technical Committee ISO/TC 67, Oil and gas industries including lower carbon energy, Subcommittee SC 7, Offshore structures, in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 12, Oil and gas industries including lower carbon energy, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This third edition cancels and replaces the second edition (ISO 19901-4:2016), which has been technically revised.

The main changes are as follows:

— guidance extended on representative and design values for soil parameters (Clause 5);
— guidance added for geotechnical design of intermediate foundations for fixed structures and clause renamed to ‘Design of shallow and intermediate foundations’ (Clause 7);
— requirements added on installation resistance, yield envelope approaches for ultimate limit state, and performance- based design for shallow skirted and intermediate foundations (Clause 7);
— new unified CPT method for axial capacity in sands to replace the former main text method, new TZ curve definition in sands, new unified CPT method for clays introduced into the Clause A.8, new PY curve methodology for clays to replace the existing method (Clause 8);
— new requirements added on reassessment of pile capacity for existing structures (Clause 9);
— a new clause for pipelines, conductors and risers (Clause 10);
— references have been reviewed, updated and reduced where possible.

A list of all parts in the ISO 19901 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

ISO 19901-4:2025

Oil and gas industries including lower carbon energy. Specific requirements for offshore structures - Geotechnical design considerations

Current

Published:

14 Feb 2025