International ISO Standard IS019901-3 Oil and gas industries including Third edition lower carbon energy - Specific 2024-01 requirements for offshore structures - Part 3: Topsides structure Industries du pétrole et du gaz, y compris les énergies a faible teneur en carbone - Exigences spécifiques relatives aux structuresenmer- Partie3:StructuresTopSides Reference number ISO 19901-3:2024(en) @ ISO 2024 IS0 19901-3:2024(en) COPYRIGHT PROTECTED DOCUMENT CIS02024 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below orIso's memberbody inthe countryofthe requester. ISO copyright office CP 40i:Ch.de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Email:[email protected] Website: www.iso.org Published in Switzerland @ IS0 2024 - All rights reserved i IS0 19901-3:2024(en) Contents Page Foreword. .vii Introduction 1 Scope. 1 2 Normative references 2 3 Terms and definitions 3 4 Symbols and abbreviated terms. 5 4.1 Symbols.. 5 4.2 Abbreviated terms. 6 5 Overall requirements. 7 5.1 Conceptual design. 7 5.2 Codes and standards 5.2.1 Limit states and allowable stress philosophies 5.2.2 Use of national building standards .8 5.3 Deck elevation 8 5.4 Exposure level 8 5.5 Operational requirements. 5.5.1 Functional requirements 9 5.5.2 Spillage and containment 9 5.6 Design physical environmental conditions 9 5.7 Critical structure. 9 5.8 Assessmentofexistingtopsidesstructure .10 5.9 Reuse of topsides structure. .10 5.10 Repairs, modifications and refurbishment. .10 6 Design requirements. 11 6.1 General .11 6.2 Design/assessment situations. .11 6.3 Material selection.. 11 6.4 Structural interfaces .11 6.5 Design for serviceability .11 6.5.1 Serviceability limits .11 6.5.2 Vibrations.. 12 6.5.3 Deflections. 13 6.6 Design for strength. .14 6.7 Design for fatigue. 14 6.8 Robustness .14 6.8.1 General .14 6.8.2 Ductility .14 6.9 Confirmation of execution of design requirements 15 6.10 Corrosioncontrol 15 6.11 Design for fabrication and inspection .16 6.12 Design for loadout, transportation and installation .16 6.13 Design for structural integrity management. .17 6.14 Design for decommissioning,removal and disposal 17 6.14.1 General .17 6.14.2 Structural releases. 17 6.14.3 Lifting appurtenances .17 6.14.4 Heavy lift and set-down operations .17 7 Actions and analysis methods 18 7.1 General .18 7.2 In-serviceactions .19 7.3 Action factors.. 20 7.3.1 Design actions for operational design/assessment situations in still water 20 IS02024-Allrightsreserved iii IS0 19901-3:2024(en) 7.3.2 Design actions for operational design/assessment situations with operating environmental actions. 20 7.3.3 Design actions for extreme design/assessment situations. 21 7.4 Vortex-inducedvibrations 21 7.5 Indirectactions and resulting forces (action effects) 21 7.6 Metocean and ice actions. 22 7.6.1 Wave, current and ice actions. 22 7.6.2 Wind actions 23 7.6.3 Cold regions effects. 24 7.7 Seismic actions .24 7.7.1 General 24 7.7.2 Minimum lateral acceleration .24 7.7.3 Equipment and appurtenances. 24 7.8 Actions during fabrication, loadout, transportation, and installation 25 7.9 Actions arising from accidental events... 25 7.9.1 General 25 7.9.2 Structural design for fire hazard. .27 7.9.3 Structural design for explosion hazard 28 7.9.4 Explosionandfireinteraction. .32 7.9.5 Cryogenic spill 33 7.9.6 Actions due to vessel collision.. 33 7.9.7 Actions due to dropped and swinging objects and projectiles 33 7.9.8 Actions due to loss of buoyancy 33 7.9.9 Actions due to topsides acceleration 34 7.10 Other actions. 34 7.10.1 Drilling 34 7.10.2 Conductors. 35 7.10.3 Risers 36 7.10.4 Caissons 36 7.10.5 Maintenance, mechanical handling and li