In-depth | STANDARDS FEATURE


Making the case for adding variety to Goal-Based Standards


Goal-Based Standards as applied by the IMO are a step forward in improving the design and operation of ships. Nonetheless, Professor Jeom Kee Paik suggests a way that the standards can be improved by taking into account forces that are variable and unexpected through health, safety, environment and ergonomic considerations


ships, emphasising that the IMO must increase its efforts to determine the overall standards for building new ships. Te original GBS concept comprises the


G


following five tiers, as shown in Figure 1: goals (Tier I); functional requirements (Tier II); verification of compliance (Tier III); regulations and rules for ships such as classification rules, IMO requirements and relevant national requirements (Tier IV); and applicable industry standards and practice (Tier V). Tiers I-III basically constitute the IMO’s GBS, and Tiers IV and V are associated with regulations and practices specified by classification societies and/or industries. Te IMO’s GBS are timely and excellent,


as they stimulate innovations in ship design technologies that help ships to remain safe throughout their design lifetimes, in accordance with relevant inspection and maintenance schemes. Te concept of the IMO’s GBS is also well suited with the scope and objective for design, building and operation of offshore installations. However, the standards require some modification to complete the concept. Ships and offshore installations usually


operate under normal conditions while in service, but can face extreme and even accidental conditions, as shown in Figure 2. Ship and offshore structures are subject to various action effects resulting from these extreme and accidental conditions. Te sources of such actions and action effects include welding induced high


Figure 1: Original IMO GBS concept with five tiers


22 The Naval Architect January 2015


oal-based standards (GBS) for ship design and construction have been applied to all types of oceangoing


temperature causing initial imperfections (e.g., initial distortions, residual stress or softening in the heat-affected zones of welded aluminium structures); abnormal waves/winds/currents; dynamic pressure loads arising from sloshing, slamming or green water; low temperature in Arctic operations; cryogenic conditions resulting from liquefied natural gas cargo; ultra-high pressure in ultra-deep waters; elevated temperature due to fire; blast loads due to explosion; impact loads associated with collision, grounding or dropped objects; and age-related degradation such as corrosion, fatigue cracking and local denting damage. Such events sometimes result in


Professor Jeom Kee Paik says the IMO’s Goal-based standards are incomplete


catastrophic consequences that lead to casualties, property damage, and pollution.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60