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95-14 Assessment of Fire, Smoke, and Toxicity Characteristics of Composite Materials Proposed for Marine Applications Objective Determine the flammability, smoke, and toxicity properties of composite materials and identity promising candidate material systems for ship and offshore platform structures designed to meet international fire-safety and envirorunental standards. Benefit The study wall provide needed understanding of the opportunities and limitations of the application of composites in compartments subject to fire hazard. It wall provide the stimulus for encouraging new matenals development and provide the opportunity to evaluate promising new fire-resistant materials. SSC National Goals Improve the safety and integrity of marine structures. Reduce marine environmental risks. SSC Strategy Prevention research, including damage-tolerant structures, structural monitonng, and human factors Background Materials used to construct and outfit commercial ships must meet stringent requirements for flammability, while still meeting nave] architectural requirements for light weight and low cost. The International Convention for the Safety of Life at Sea, 1974, as amended, requires the hull, superstructure, structural bulkheads, decks, and deckhouse to be constructed of steed or other equivalent matenals. "Equivalent matenals" is further defined in the convention as any noncombustible matena] that by itself or because of insulation provided, has structural and integrity properties equivalent to those of steed at the end of standard fire tests. Further requirements are also established for bulkhead, ceiling, and deck matenals. The lack of generation of smoke and tome combustion products in a fire is also important for successful fire safety. Paradigms about the performance of composite matenals in a fire are often inconsistent with test results. Tests on fberglass/epoxy pipe, for example, have demonstrated the safety meets of the use of fiberglass pipe in firewater systems on onshore platforms, and fiberglass/epoxy firemain pipes are now used in most parts of the world, including the United States, the North Sea, and the Middle East. Me United States, Norway, and the United Kingdom are highly active in assessing the safety of materials in a fire safety, and this project should take advantage of U.S. and foreign developments to ensure that the study does not duplicate prior efforts. The program should concentrate on commercially available materials. Phenolic resins have shown promise in past studies; however, a host of new materials have recently become available, including several manufactured in the United States. The workshop sponsored by the SSC entitled "Use of Composite Materials in Load-Beanng Manne Structures" (SR-1331) strongly recommended that work be done on s7

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the fire characterization of composite materials, including their flammability, smoke, and toxicity properties. Recommendations Survey the existing data base on fire performance of composite materials, including data from non-U.S. programs. The contractor should also solicit industry for promising new fire-resistant materials with low smoke and toxicity charactenstics. This survey should consider matrix resins as well as insulation materials and include all possible solutions, including thermoses and thermoplastic resins and phenolic-based materials. Survey and identity appropriate test methods for evaluating the performance of composite materials for marine structural applications. Conduct fire, smoke, and toxicity tests on promising new materials for which data are not available. Identity applications where fire-resistant composite matenais could provide enhanced safety, structural efficiency, and competitive economical advantage. For example, a fire-resistant resin might be used to construct pipe that would be sufficiently fire resistant that it did not require separate fire-protection insulation for dry Remain pipe application. Other examples might include a composite structural frame or bulkhead, composite deckhouse, or accommodation module. From a human-factors viewpoint and considering fire and smoke standards, recommend maximum acceptable smoke and toxicity threshold levels for the applications studied above. Duration 4,000 labor hours over 2 years 95-15 High Productivity Welding Processes (9413) Objective Reduce new ship construction costs and improve weld property control through automation of welding processes. Benefit The data developed by this project wall provide information to shipyards and allow them to (~) better develop new processes for higher productivity welding and (2) assess the improvements inherent In automated processes particularly in weld geometry control that improve ship integrity. This work will assist shipyards in obtaining code and Industry acceptance of the new procedures and wall develop methods of using the higher- quality processes. SSC National Goal Support the U.S. maritime industry in shipbuilding, maintenance, and repair. SSC Strategy Development of structures-related producibility technology 58

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Background In recent years, improvements in utilizing conventional welding processes have enhanced productivity. While the U.S. industry in the last decade has been concentrating on Navy ship construction, European and Japanese shipyards have advanced automation in commercial ship construction, which is more readily adapted to such methods. It is essential that the domestic shipyards move from the facilities optimized for high flexibility and di~cult-to-weld materials in Navy construction to commercial ship construction, which emphasizes highly repetitive producible designs that use materials that are more readily welded. A rigorous assessment of the state of the art In foreign shipyards and related industries should add to the high-productiv~ty methods now used in the U.S. heavy industry. Application of these techniques to domestic shipyards should improve the productivity of fabrication ~ commercial and military ships. Automated methods produce more consistent and controlled weld geometries. This improved eeometn has better fatigue nerfonnance than that produced hv In . _ ~ ~ 1 ~ r~~~~~~ J ~ and semiautomatic methods. The automated processes wall also control thermal parameters better to reduce vanability in weldment properties. A methodical and quantitative study of the venous improvements in fabrication and welding processes should provide the domestic shipbuilding Must th a bench- mark to assist planning for new automated facilities. Me impact of automation on weldment properties could lead to designs that are more cost-effective. Recommendations Perform the following tasks: Identifier and catalog recent productivity improvements (new electrodes, procedures, and gas mixtures) in commercial welding processes, and identifier the state of the art In automation in the foreign shipbuilding industry, such as gantry robotics; portable robotics; portable mechanized equipment; new high-speed butt-welding processes; and adaptive controls for seam tracking, fill, and penetration control. Based on available data, assess the improvements possible in venous processes used by the industry for specific welding tasks in ship construction. Define benefits and trade-offs in terms of deposition rate, operating characteristics, and other welding factors that affect productivity. Note effects on weld quality (e.g., improved process control and better control of weldment geometry and properties), and develop sufficient background information to permit designers to take better advantage of the improved consistency of automated welds. Prepare a quantitative report for use by the marine industry, with the potential to assess cost savings and code acceptance. Duration 2,000 labor hours over 2 years 95-16 Evaluation of Marine Structures Education in North America Objective Provide the knowledge needed for the SSC to wisely and effectively take steps to improve the structural engineering departments in North American colleges and universities In support of ship structural design. so

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Benefit The project wall result in improved training In ship structural design and construction and hence improved ship structural designs and international competitiveness of the U.S. shipbuilding industry. SSC National Goals Improve the safety and integrity of marine structures. Reduce marine environmental risks. Support the U.S. maritime industry in shipbuilding, maintenance, and repair. SSC Strategy Sponsoring university research in areas such as design tools development, Producibility, production Drocesses. reliability design. and dama~e-tolerant structures O _ ~ Background In many instances, ship structural designers have either undergraduate or graduate degrees, or both, in civil engineering. Therefore, all applicable aspects of structural eng~neenng are included in this discussion of ship structural design. The SSC has officially recognized in its strategic plan that healthy, capable schools teaching modern methods of ship structural design and construction are essential to sustaining and improving the international competitiveness of the U.S. ship design and construction industry. At the same time, the SSC has recognized that the extent and quality of ship structural engineering education has apparently declined in recent years and has indicated a desire to take steps to improve the situation. Reasons for the decline noted above seem to include the genera] decline of eng~neenng as a career choice of talented high school students. In addition, the decline of commercial shipbuilding in the U.S. has had two effectsa decline In the number of students attracted to ship structural design as a career choice and a decline in the pool of faculty candidates with relevant ship structural design experience. Furthermore, the reduction in government and industry support for university research in ship structure research and development has decreased the number of faculty members who specialize in this area. The SSC must be armed with facts concerning the current status of and trends in ship structural design and construction education before it can make proper decisions on how to improve the situation. Recommendations Perform the following tasks: Perform a study to assess the current status of applicable ship structural design and construction training in North America and trends in the condition of that training. Address both undergraduate and graduate programs at public and private institutions. Utilize external resources such as Accreditation Board for Engineering and Technology and the Education Committee of the Society of Naval Architects and Marine Engineers as well as direct contact with the institutions themselves. Develop a set of questions that can be asked of each institution to gain a comprehensive understanding of the situation. Examples of topics about which questions might be asked are I. the annual number of graduates who have majored in ship structural design and recent trends; 60

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2. the annual number of students attending ship structural design courses and recent trends; 3. courses offered In ship structural design and ship construction; 4. the content of the shin structural design and ship construction courses offered; 5. the balance between theoretical and practical design courses; 6. design projects required (length, scope, individual versus team efforts, etc.~; 7. practical work experience required; 8. lab work required; 9. industry experience of facula in ship structural design; 10. faculty experience in ship structural design research and development; Il. industry experience of faculty in ship construction; 12. emphasis given in curriculum to ship production and producibility of structural designs; 13. emphasis given to economic aspects and cost-effectiveness trade-offs in ship structural design; and 14. emphasis given to the relationship between ship structural design and total ship system design. Perform an analysis of the survey results to develop a comprehensive picture of the current status of ship structural design and construction education in North America. Identitr major deficiencies and problem areas. Develop a set of recommendations for SSC actions that would help to correct the major problems identified. Duration 1,000 labor hours over ~ year 61

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62 RESEAlRCHRECOMMENDATIONS FOR FYs 1998-1999 SR-1368 Compensation for Openings in Structural Members Investigator John Hopkinson Contractor Vibtech, Inc., North Kingstown, Rhode Island Objective Establish rational methodologies and guidelines for the determination of appropriate compensation for small and large openings in primary structural members of ships. Two sets of guidelines are required, one suitable for oreliminarv and contract design and another for detailed design. The efficiency and reliability of structural reinforcements around openings In primary structures should be improved and their design ant! construction should be made less costly. Project Chair Stephen G. Arntson, Arlington, Virginia Technical Adviser none assigned SR-1369 Fleet of the Future Publication Review I~lYlesti.~llor~.~ohn w Fisher C`)ntr~.tor Lehigh University, Bethlehem' Pennsylvania Objective Review the work published by the Center for Advanced Technology for Large Structural Systems of Lehigh University under the U. S. Navy- sponsored "Fleet-of-the-Future" program. Summarize the material in a single volume and publish it as an SSC report. Project Chair William I. Siekierka, Naval Sea Systems Command, Arlington, Virginia Technical Adviser none assigned SR-1374 A Guide to Damage Tolerance Analysis of Marine Structures Investigator LalitMalik Contractor Fleet Technology Tnc., Kanata, Ontario, Canada

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ACTIVE AND PENDING PROJECTS This section covers current projects funded with FY 1992 (or earlier) funds, those continued with FY 1993 funds, and those that will be supported with FY 1994 funds. They constitute the current program. The majority of projects are for one year; multlyear projects are funded incrementally on an annual basis. Project descriptions include the project number and title, the name of the pnncipal investigator and organization (when determined), a brief statement of the project's objective, and the names of project chairmen and technical advisers (when assigned). 63

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TABLE 4 Active and Pending Projects Number Project Title SR-1300 Evaluation of a Generalized Onboard Response Monitoring System (Phase 2) SR-1335 Interactive Nature of Cathodic Polarization and Fatigue SR-1338 Uncertainty in Strength Models for Manne Structures SR-1339 Effect of High-strength Steels on Strength Considerations of Design and Construction Details of Ships . . . . .. . . . . . . . . . . . . . . . . SR-1341 Residual Strength Assessment for Damaged Marine Structures SR-1342 Hydrodynamic Impact on Displacement Ship Hulls .. SR-1343 Optimized Weld Metal Properties for Ship Structures . . . SR-1344 SR-1345 Assessment of Reliability of Existing Ship Structures (Phase 2) Probability-based Design (Phase 3~: Implementation of Design Guidelines for Ships . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . SR-1346 Improved Ship Hull Structural Details Relative to Fatigue SR-1348 Measurement of Ice Loads on Ship Structures . .... . . SR-1349 Evaluation of Ductile Fracture Models for the Prediction of Fracture Behavior of Ship Structure Details SR-1350 Reexamination of Design Criteria for Stiffened Plate Panels . . . . . . . SR-1351 Hull Structure Concepts for Improved Producibility SR-1353 The Role of Human Error in the Design, Construction, and Reliability of Manne Structures SR-1354 Grounding Protection of Tankers SR-1355 Inspection of Marine Structures SR-1356 SR-1357 SR-1358 SR-1359 SR-1360 SR-1362 . Strength Assessment of Pitted Plate Panels Retention of Weld Metal Properties and Hydrogen Cracking Optimized Design Parameters for Welded TMCP Steels . . . . U.S.-Russian Cooperative Research Effort .. .... ... . ..... Structural Maintenance Project Probability Based Design (Phase 4), Synthesis of the Reliability Thrust Area 72 SR-1363 Symposium and Workshop on the Prevention of Fracture in Ship Structures 73 73 Page 65 65 65 66 66 66 67 67 67 68 68 68 69 69 69 70 70 70 71 71 72 72 SR-1364 Guidelines for Evaluation of Finite Element Models and Results SR-1365 Optimal Strategies for Inspection of Ships for Fatigue and/or Corrosion Damage SR-1366 Corrosion Control of Inner-Hull Spaces . . . . SR-1367 Design Guide for Marine Applications of Composites SR-1368 Compensation for Openings in Structural Members 73 ........ 74 74 75 64

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SR-1300 (Phase 2) Evaluation of a Generalized Onboard Response Monitoring System Investigator Jack W. Lewis Contractor ARCHAIC Offshore Corporation, Escondido, California Objective Evaluate a generalized operations-oriented stress and motion monitoring system under shipboard operating conditions. Project Chairman Walter M. Maclean, U.S. Merchant Marine Academy, Kings Point, New York Technical Adviser C. B. Walburn, Bethlehem Steel Corporation, Sparrows Point, Maryland SR-1335 Interactive Nature of Cathodic Polarization and Fatigue Investigator Car] E. Jaske Contractor Cortest Columbus Technologies Inc., Columbus, Ohio Objective Investigate the effects of cathodic polarization on fatigue of steel in seawater and how cathodic polanzation is influenced by notch severity, crack size, and material composition and microstructure (steed strength). Project Chainnan William Hanzalek, American Bureau of Shipping, Houston, Texas Technical Adviser William H. Hartt, F1orida Atlantic University, Boca Raton SR-1338 Uncertainty in Strength Models for Marine Structures Investigator Owen Hughes Contractor Ross/McNatt Naval Architects, Stevensv~le, Maryland Objective Quantify bias and uncertainty in structural strength formulations In order to evaluate safety margins and derive design criteria. Project Chairman Rickard Anderson, Military Sealift Command, Washington, D.C. Technical Adviser Paul H. Wirsching, University of Arizona' Tucson 6s

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SR-1339 Effect of High-strength Steels on Strength Considerations of Design and Construction Details of Ships Investigator Peter W. Buermann Contractor Gibbs & Cox, Inc., New York, New York Objective Analyze the in-service failures in construction details using high-strength steels, identifier problem areas, and recommend design and construction details to reduce problems. Project Chairman Philip G. Rynn, American Bureau of Shipping, Houston, Texas Technical Adviser Roger G. Kline, Consultant Ship Structures, New Berlin, Wisconsin SR-1341 Residual Strength Assessment for Damaged Manne Structures Investigator Christopher J. Wiernicki Contractor Designers and Planners, Inc., Arlington, Virginia Objective Develop approaches to assess the residual strength and life of marine structures that have sustained damage in service. Project Chairman John S. Spencer, American Bureau of Shipping, Houston, Texas Technical Adviser Maria Celia C. Ximenes, Chevron Shipping Company, San Francisco, California SR-1342 lIydrodynamic Impact on Displacement Ship EIulis Investigator John C. Daidola Contractor M. Rosenblatt & Son, New York, New York Objective Assess the state of the art in estimating forebody hydrodynamic impacts on displacement ship hulls, and develop a plan for future research on hydrodynamic impact loadings on marine structures. The plan must address slamming, wave slap, and Frontal impacts. Project Chairman Allen H. Engle, Naval Sea Systems Command, Washington, D.C. 66

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Technical Adviser Subrata K. Chakrabarti, Chicago Bndge & Iron Co., Plainfield, Illinois SR-1343 Optimized Weld Metal Properties for Ship Structures Investigator Robert J. Dexter Contractor Advanced Technology for Large Structural Systems Engineering Research Center' Lehigh University' Bethlehem' Pennsylvania Objective Develop guidelines to improve productivity by optimizing weld-metal properties for use with high-strength steels. Project Chairman J. Allen Manuel, Naval Sea Systems Command, Arlington, Virginia Technical Adviser James M. Sawhill, Jr., Newport News Shipbuilding, Newport News, Virginia SR-1344 Assessment of Reliability of Existing Ship Structures (Phase 2) Investigators Alaa Mansour Contractor Mansour Engineering, Inc., Berkeley, CalifoInia Objective Estimate reliability levels associated with important failure modes of existing ship structures. Project Chairman Robert A. Sielski, Manne Board, Washington, D.C. Technical Advisers Keith Hjelmstad, University of lIlinois, Urbana; Solomon C.S. Yim, Oregon State University, Corvallis SR-1345 Probability-based Design (Phase 31: Implementation of Design Guidelines for Ships Investigator not yet determined Contractor not yet determined Objective Develop a prototype probability-based design or safety-checking criteria for ships. 67

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Project Chairman Bill Richardson, Carderock Division, Naval Surface Warfare Center, Carderock, Maryland Technical Adviser Achintya Haldar, University of Arizona, Tucson SR-1346 Improved Ship Elull Structural Details Relative to Fatigue Investigator Karl Stambaugh Contractor Consulting Naval Architects, Severna Park, Maryland Objective Develop a series of improved structural details that accounts for the unique fatigue stress pattern of ship structures. Project Chairman Chao Lin, U.S. Mantle Administration, Washington, D.C. Technical Adviser Robert L. Clark, ClarkCim, Inc., Reston, Virginia SR-1348 Measurement of Ice Loads on Ship Structures Investigator J.W. St. John Contractor Science Technology Corporation, Columbia, Maryland Objective Develop a data base on ice loads that could be used for probability-based design approaches. Assess the effects of ship displacement, impact location, and hull shape on the ice impact loads on icebreakers and other marine structures. Project Chairman Rubin Sheinberg, U.S. Coast Guard, Washington, D.C. Technical Adviser none assigned SR 1349 Evaluation of Ductile Fracture Models for the Prediction of Fracture Behavior of Ship Structure Details Investigator Robert J. Dexter Contractor Lehigh University, Bethlehem, Pennsylvania Objective Establish the effectiveness of ductile fracture mechanics models for predicting the fracture behavior of component ship-structure details. 68