Structural Design of Offshore Structures: A Review of Indian and International Standards

Year : 2026 | Volume : 13 | Issue : 13 | Page : 36 51
By

Er. Syed Shafahaduddin Quadri,

  1. , Senior Structural Engineer, Quadri Consultant, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad, Maharashtra, India, ,

Abstract

Offshore structures—including fixed steel jackets, topside modules, offshore wind turbine support structures, and floating systems—are designed to withstand combined gravity, environmental, seismic, and operational loads under substantial uncertainty and limited access for inspection and repair. Structural design practice has historically relied on internationally recognized standards, particularly the American Petroleum Institute’s API RP 2A, the International Organization for Standardization’s ISO 19900 series, including ISO 19902 for fixed steel structures, and Det Norske Veritas (DNV) standards, together with regional provisions such as NORSOK and DNV ST-0126 for offshore wind turbine support structures. In India, offshore development, particularly by the Oil and Natural Gas Corporation (ONGC) in the Western Offshore basin, has predominantly followed API RP 2A working stress design principles, supplemented by IS 800 and in-house engineering practices developed by ONGC’s Institute of Engineering and Ocean Technology (IEOT). This paper presents a systematic review of thirty studies, standards, and technical reports addressing offshore structural design and integrity assessment. The reviewed literature is organized into six thematic areas: design philosophies and API/ISO code evolution; cross-code comparisons; fatigue design and S-N curve provisions; reliability-based load and resistance factor calibration; offshore wind turbine support-structure standards; and structural integrity, life extension, and Indian offshore applications. The review indicates that API RP 2A and ISO 19902 share fundamental approaches to tubular-member and joint-strength assessment, while differences in safety-factor philosophies, environmental load factors, and regional calibration can lead to variations in predicted structural reliability. The findings also demonstrate that these standards continue to evolve in response to reliability, safety, and emerging offshore applications. Indian offshore practice faces the additional challenge of reconciling API-based design with IS 800 requirements and the structural integrity and life-extension needs of ageing platforms. Furthermore, India’s emerging offshore wind sector requires adaptation of established oil-and-gas design practices to turbine-specific international standards, as a dedicated domestic standard is not yet established. Based on the identified evidence gaps, the study proposes a focused research agenda covering India-specific environmental load factors, reliability calibration, code harmonization, ageing-platform assessment, and offshore wind support structures. The review provides a foundation for future research aimed at improving the safety, reliability, and sustainability of offshore infrastructure in India.

Keywords: Offshore structures, API RP 2A, ISO 19902, DNV, IS 800, working stress design, load and resistance factor design, reliability index, fatigue design, structural integrity assessment, risk-based inspection, offshore wind turbine support structures, Indian offshore standards

[This article belongs to Journal of Offshore Structure and Technology ]

How to cite this article: Er. Syed Shafahaduddin Quadri. Structural Design of Offshore Structures: A Review of Indian and International Standards. Journal of Offshore Structure and Technology. 2026; 13(13):36-51.
How to cite this URL: Er. Syed Shafahaduddin Quadri. Structural Design of Offshore Structures: A Review of Indian and International Standards. Journal of Offshore Structure and Technology. 2026; 13(13):36-51. Available from: https://journals.stmjournals.com/joost/article=2026/view=257655

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Regular Issue Subscription Review Article
Volume 13
Issue 13
Received 30/07/2026
Accepted 08/08/2026
Published 12/08/2026
Publication Time 13 Days

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