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www.sname.org/sname/mt April 2013 intensity, restriction of heat release rate resulting from ventilation shortage, occur- rence of ashover, and the nal decay are key processes modeled in the current approach. They are interfaced with fire suppression triggered by detection. e eect of manual intervention is also assessed. An application is included based on uniform distributions of selected random parameters. Justication for the considered ranges is provided. e eect of assuming dierent probability distributions is considered. e methodology can be used for producing the probability of containment and extinguishment of res as well as for judg- ing the performance of an overall or partial ship design solution.Response of IACS URI Ship Structures to Real-time Full-scale Operational Ice Loads BY BRUCE W.T. QUINTON, CLAUDE G. DALEY, AND ROBERT E. GAGNON PUBLISHED IN ICETECH PROCEEDINGS Moving ice loads can incite signicantly dif -ferent structural responses in a steel grillage structure than can stationary ice loads. is is signicant because the accepted standard for the design and analysis of ice-classed ship structures is to assume a stationary ice load (IACS URI I2.3.1). e following work uses the 4D Pressure Method (Quinton, Daley, and Gagnon 2012) to apply 35 of the most signif- icant ice loads recorded during the USCGC Polar Sea trials (1982-86), to 14 IACS URI PC1-7 classed grillages, using explicit nite element analyses. Two grillage variations for each of the seven PC classes were examined: grillages with built T? framing and grillages with flatbar? framing. In short, the simu- lations outlined directly employ real-time/ real-space measured full-scale ice loads, and thus provide insight into the structural capa- bilities of the various IACS URI polar classes when subject to actual (moving) ice loads. Arctic Oshore Structure EER Risk Based Standards and Methods of Risk Analysis BY JAMES P. POPLIN AND FRANK G. BERCHA PUBLISHED IN ICETECH PROCEEDINGS e Canadian Oshore Structure Performance Based EER Standards 2006 and International Standard ISO 19906 Arctic Oshore Structures 2010 were developed to help ensure that o- shore structures deployed where arctic conditions prevail, provide the appropriate level of reliability with respect to personnel safety, environmental protection, and asset value. Both standards address escape, evac- uation, and rescue (EER). The Canadian standard provides reliability targets for key elements and the totality of the EER process, whereas the ISO standard addresses design, construction, transportation, installation, and decommissioning phases of the structure. EER is a system that mitigates the eects of major accident hazards to personnel. A suite of risk analyses methodologies are typically employed to assess the EER philosophy and to conrm the provisions of the overall EER system design. e objectives of such analy- ses are to assess the design adequacy (from an EER perspective) at key stages in the design, to assess the impact of changes to the design that are proposed, and to demonstrate that risks to personnel in the overall design are as low as reasonably practicable. Following a general description of the Canadian and ISO standards EER risk and reliability-based pro- visions, this paper provides an overview of some of the applicable risk methodologies including the EER analysis. Development of Composite Sandwich Structures for Arctic Region BY K.M.A. SOHEL, J.Y. RICHARD LIEW, YAN JIABAO, M.H. ZHANG, AND P.W. MARSHALL PUBLISHED IN ICETECH PROCEEDINGS A cone shaped steel-concrete composite struc- ture has been proposed for arctic offshore structures. is type of cone structure is able to withstand the ice forces imposed thereon by impinging ice sheets and other larger masses of ice wherein the structure has an upper conical portion coaxially positioned rela- tive to a lower cylindrical portion. is study explores the use of the curved steel concrete steel (SCS) sandwich system in the proposed arctic cone structure. e SCS sandwich sys- tem, which combines the beneficial effects of steel and concrete materials, has shown promising benets over conventional plates and stieners design and heavily reinforced concrete design because of its high strength to weight ratio. Shear connectors have been proposed to connect steel face plates and cementitious core material. e proposed SCS sandwich system can reduce structural com- plexity, particularly the number of weld joints which are prone to fatigue and corrosion. is can increase service life, cut down the cost of fabrication, and reduce the manpower cost to operate, inspect, and maintain the structure in the long run. Considering local ice load, the punching shear strength of the SCS sandwich composite shell was studied experimentally. e SCS specimens were designed using the ISO ice pressure. The experimental results show that they possess far higher resistance against patch load caused by ice. Moreover, the load-deection behavior of the curved SCS sandwich system is ductile and it can absorb a great deal of energy at failure. Risk Based Approach to Operational Iceberg Management BY JIM BRUCE, FREEMAN RALPH, AND PAUL STUCKEY PUBLISHED IN ICETECH PROCEEDINGS Oil and gas exploration activities in iceberg- populated waters require careful planning to ensure operations are conducted with the utmost attention to safety and environmental protection while minimizing iceberg-related downtime. is paper describes a methodol- ogy for estimating downtime and providing a tool to plan ice management eet require- ments for operations. MTGO DEEPER Both the Journal of Ship Production and Design and the Journal of Ship Research are available by subscription. Go to www.sname.org/SNAME/Pubs/Journals1/ and ?nd out why these technical journals are indispensable to naval architects and marine engineers around the world.