ISO 19905-1:2012

Petroleum and natural gas industries — Site-specific assessment of mobile offshore units — Part 1: Jack-ups

ISO 19905-1:2012 specifies requirements and guidance for the site-specific assessment of independent leg jack‑up units for use in the petroleum and natural gas industries. It addresses manned non-evacuated, manned evacuated and unmanned jack‑ups; the installed phase at a specific site. To ensure acceptable reliability, the provisions of ISO 19905-1:2012 form an integrated approach, which is used in its entirety for the site-specific assessment of a jack‑up. ISO 19905-1:2012 does not apply specifically to mobile offshore drilling units operating in regions subject to sea ice and icebergs. When assessing a jack-up operating in such areas, it is intended that the assessor supplement the provisions of ISO 19905-1:2012 with the provisions relating to ice actions and procedures for ice management contained in ISO 19906. ISO 19905-1:2012 does not address design, transportation to and from site, or installation and removal from site. However, it is advisable that the assumptions used in the assessment be checked against the as-installed configuration. To ensure that the design of the jack‑up is sound and the structure is adequately maintained, ISO 19905-1:2012 is applicable only to independent leg jack‑ups that either: hold a valid classification society certification from a recognized classification society (RCS) throughout the duration of the operation at the specific site subject to assessment, or have been verified by an independent competent body to be structurally fit for purpose for elevated situations and are subject to periodic inspection, both to the standards of an RCS. Jack‑ups that do not comply with this requirement are assessed according to the provisions of ISO 19902, supplemented by methodologies from ISO 19905-1:2012, where applicable.

Industries du pétrole et du gaz naturel — Évaluation spécifique au site d'unités mobiles en mer — Partie 1: Plates-formes auto-élévatrices

General Information

• Status: Withdrawn
• Publication Date: 24-Jul-2012
• Withdrawal Date: 24-Jul-2012
• ICS: 75.180.10 - Exploratory, drilling and extraction equipment
• Technical Committee: ISO/TC 67/SC 7 - Offshore structures
• Drafting Committee: ISO/TC 67/SC 7/WG 7 - Site specific assessment of mobile offshore units (MOUS)
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 15-Jan-2016
• Completion Date: 15-Jan-2016

Relations

• Consolidates: ISO 8434-5:1995 - Metallic tube connections for fluid power and general use — Part 5: Test methods for threaded hydraulic fluid power connections
• Effective Date: 06-Jun-2022
• Revised: ISO 19905-1:2016 - Petroleum and natural gas industries — Site-specific assessment of mobile offshore units — Part 1: Jack-ups
• Effective Date: 04-Nov-2015

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 19905-1
First edition
2012-08-01
Petroleum and natural gas industries —
Site-specific assessment of mobile
offshore units —
Part 1:
Jack-ups
Industries du pétrole et du gaz naturel — Évaluation spécifique au site
d'unités mobiles en mer —
Partie 1: Plates-formes auto-élévatrices

Reference number
©
ISO 2012
©  ISO 2012
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ii © ISO 2012 – All rights reserved

Contents Page
Foreword . v
Introduction . vii
1  Scope . 1
2  Normative references . 2
3  Terms and definitions . 2
4  Symbols and abbreviated terms . 13
4.1  Symbols . 13
4.2  Abbreviated terms . 14
5  Overall considerations . 15
5.1  General . 15
5.2  Assessment approach . 16
5.3  Selection of limit states . 18
5.4  Determination of assessment situations . 18
5.5  Exposure levels . 20
5.6  Analytical tools . 23
6  Data to assemble for each site . 24
6.1  Applicability . 24
6.2  Jack-up data . 24
6.3  Site and operational data . 24
6.4  Metocean data . 24
6.5  Geophysical and geotechnical data . 25
6.6  Earthquake data . 26
7  Actions. 26
7.1  Applicability . 26
7.2  General . 26
7.3  Metocean actions . 27
7.4  Functional actions . 28
7.5  Displacement dependent effects . 28
7.6  Dynamic effects . 28
7.7  Earthquakes . 28
7.8  Other actions . 28
8  Structural modelling . 28
8.1  Applicability . 28
8.2  Overall considerations . 28
8.3  Modelling the leg . 29
8.4  Modelling the hull . 30
8.5  Modelling the leg-to-hull connection . 30
8.6  Modelling the spudcan and foundation . 31
8.7  Mass modelling . 32
8.8  Application of actions . 32
9  Foundations . 35
9.1  Applicability . 35
9.2  General . 35
9.3  Geotechnical analysis of independent leg foundations . 36
9.4  Other considerations . 39
10  Structural response . 41
10.1  Applicability . 41
10.2  General considerations .41
10.3  Types of analyses and associated methods .41
10.4  Common parameters .42
10.5  Storm analysis .44
10.6  Fatigue analysis .47
10.7  Earthquake analysis .47
10.8  Accidental situations .47
10.9  Alternative analysis methods .48
11  Long-term applications .48
11.1  Applicability .48
11.2  Assessment data .48
11.3  Special requirements .49
11.4  Survey requirements .50
12  Structural strength.50
12.1  Applicability .50
12.2  Classification of member cross-sections .51
12.3  Section properties of non-circular prismatic members .52
12.4  Effects of axial force on bending moment .53
12.5  Strength of tubular members .53
12.6  Strength of non-circular prismatic members .53
12.7  Assessment of joints .53
13  Acceptance criteria .54
13.1  Applicability .54
13.2  General formulation of the assessment check .55
13.3  Leg strength assessment .55
13.4  Spudcan strength assessment .56
13.5  Holding system strength assessment .56
13.6  Hull elevation assessment .56
13.7  Leg length reserve assessment .56
13.8  Overturning stability assessment .57
13.9  Foundation integrity assessment .57
13.10  Interaction with adjacent infrastructure .58
13.11  Temperatures .59
Annex A (informative) Additional information and guidance .60
Annex B (normative) Summary of partial action and partial resistance factors . 238
Annex C (informative) Additional information on structural modelling and response analysis . 240
Annex D (informative) Foundations — Recommendations for the acquisition of site-specific
geotechnical data. 250
Annex E (informative) Foundations — Additional information and alternative approaches . 256
Annex F (informative) Informative annex on Clause A.12 — Structural strength . 269
Annex G (informative) Contents list for typical site-specific assessment report . 283
Annex H (informative) Regional information . 290
Bibliography . 299

iv © ISO 2012 – All rights reserved

Foreword
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(ISO member bodies). The work of pr
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