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Hr.P. M. Palermo Nr. J. B. GregoryExecutiveirector Chief,Researchb DevelopmentaffShipDaaign& Integration of Planning& AaaeesmentDirectorate U.S.GeologicaluweyNavelSss SystemsCmmandMr.W. N. Nannan Nr.ThomasW. AllenVicePresident ChiefEngineeringfficerAmericanBureauof Shipping MilitarySealiftComand

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T h i s s t u d y c o n s t i t u t e s a l o o k a t t ! l e l o n ~ - r a n g e n e e d s a n d o p p o r t u n i t i e s t o i m-p r o v e s h i p s t r u c t u r e t h r o u g h r e s e a r c h a n d d e v e l o p me n t i n i t i a t e d b e t we e n n o w a n dA . D . 2 0 0 0 . E i g h t d i f f e r e n t t y p e s o f t r e n d s we r e r e v i e we d a l o n g wi t h t h e i r i mp l i c a t if o ] m t h e ma r i t i me i n d u s t r y : T e c h n o l o g i c a l i n n o v a t i o n s , r e s o u r c e a v a i l a b i l i t y , t r e n d si n s h i p / p l a t f o r m t y p e s a n d p o p u l a t i o n s , p o l i t i c a l , l e g a l , e c o n o mi c , mi l i t a r y , a n de n v i r o n me n t a l . E i g h t y - f i v e wo r k p a r c e l s ( a mu t u a l l y s u p p o r t i n g s e t o f R & D t a k s wh i c, a r e e s s e n t i a l c o mp o n e n t s f o r a c h i e v i n g a s p e c i f i d g o a l ) h a v e been ranked in fourlgroups-- T o p , Se c o n d , T h i r d a n d F o u r t h - - o n t h e b a s i s o f t h e i r j u d g e d i mp o r t a n c e .T h e r e p o r t h a s s e v e n c o n c l u s i o n s , a mo n g t h e m b e i n g : . . . t h a t t h e n a t i o nwi l l b e n e f i t mo s t f r o m s t r u c t u r a l i mp r o v e me ~ t s t o t h e l J a v y / n a t i o n a l d e f e n s e , o i la n d g a s , a n d t r a n s p o r t a t i o n s y s t e ms . S e c o n d l y , a n a l y s e s r e v e a l e d t h a t t h e n a t i o n a lI v a l ue of structural improvement wi 11 be greatest for i mp r o v eme n t s t o me d i u r n - s i z e dr n o n o h u l l s , s e mi s u b me r s i b l e s , l a r g e mo n o h u l l s a n d b o t t o m- mo u n t e d p l a t f o r ms , i n t h a to r d e r .

17. Key Words lR. Dis:~ibufiomta~emenrT h s d o c u me n t i s a v a i l a b l e t o t h e u . S.! p u b l i c t h r o u g h - t h e Na t i o n a l T e c h n i c a lI n f o r ma t i o n Se r v i c e , S p r i n g f i e l d ,V a . 2 2 1 6 1I19..lccurltylass,l..lh , s r-port) ~. Secuti?yCloss,f. [of Ih,spage) 21. Na. nlpagcs 22. Price

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InzhdmiyA,on Jme 24, 25 and 26, 1980,and was attended by approximately 150 peoplerepresenting indwtry, academia and involved government organizations. Thesecond workshop took place in Washington, D.C., on Decembr 18-19, 1980, andwas attended only by the Session Chairmen, Panel Moderators and WorkshopSupport Committee of the first workshop.

First Workshop: June 1980~ facilitate group interaction, the general session group at the

workshops was broken down into seven panels, one for each of the broad goalareas of the Ship Structure Committee. Each panel, consisting of approximately15 panel members , was directed by a Session ~airman. These individuals weresenior technical ~ople with broad research planning and management backgromdsrelated to structural research efforts. They led the panel members at theJune workshop in review and assessment of the position papers, tec~ical fore-casts, and candidate research projects. To assist in clarification andlogistic control, a Panel Moderator

-To provide a commcn basis

assisted the Session Chairmen.

for discussion, working papers were mailedto all participants prior to the first workshop for comment. This set ofworking papers included the technical forecasts and the position ~per forthe panel metiers assigned goal area. Revised working papers, incorporatingall co~nts and corrections provided by the participants, were completed foruse at the workshop sessions and were issued again at the workshop along with formsfor proposing candidate projects. A document describing the evaluation proce-dures to be used for scoring the projects was also provided.

each

Working PlanThe workshop agenda consisted of concurrent panel sessions addressing

of the following topics:q State of the Art - The position papers were reviewed for

adequacy in order to establish a commn basis for discussions.q Future Trends - The technical forecasts consisting of ~tential

scenarios and trends that may impact structural research require-ments were discussed. From these discussions emerged a basisfor assessing the applicability of candidate structural researchprojects to the future needs of the maritime conmmnity.

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q Project Identification Previously identified candidateprojects were reviewed for adequacy, new projects that -reflected the discussions of the position papers and technicalforecasts we~e proposed and projects no longer indicated esworthwhile were set aside. From this process emerged themost significant program areas and the 20 or 30 most signi-ficant projects as perceived by the panel for each of the goalareas.

q Project Scoring Method - A review was conducted of the evaluationmethodology to be implemented by the participants by mail forscoring the nmst significant projects.

In addition, general Sessions were conducted at the completion ofeach of the three workshop days. The general sessions consisted of presenta-tions by each of the Session Chairmen on the progress attained in their panel.This exchange provided all the participants with a perspectiw of the keyconsiderations identified in each of the panel discussions.

The final output of the first workshop was:1. A final position paper presenting the current S t a t e of the

art in each goal area, including a description of problemareas.2. A complete Technical forecast indicating the consensus of

direction for coordinated research efforts for all goal areas.3. A description and subjective assessment of the most significantprograms and 20-30 most significant projects for each of the

goal areas.Second Workshop: Decem&r 1980Z?L&

The research projects developed at the Juneeach n-rically rated by the workshop participants in

1980 workshop werethe weeks following

according to the eval-tion methodology called the project rating system.First the participants rated nine costhnefit parameters for each projectfor each of the *O time frames -- near texm and long temu. The resultsof the ratings were then fed into a computer algorithm that gave overallratings for each project and then ranked the projects individually in severalways based upon different emphasis parameters. The output resulti of thefirst workshop and these rankings provided the inputs to the secmid workshop.

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Working PlanThe second workshop agenda consisted of general sessions for SSC

goal area interaction and concurrent panel sessions f~r individual goala rea s in o rde r to:

9

TheResearch Plan

q

q

R@View and Reconcile Workshop I Participants Output - ASpart of Workshop I, key problem areas and candidate projectshad been identified and a relative order of priorit] s&jectively determined. Subsequent to Workshop I, a quantita-tive project rating system was implemented via mail. Areview and reconciliation of these prioritizations tookplace for each goal area by the Panel Chairman and Moderator.Update LRRP Procedures - The Advanced Concepts Panel Chairmanand Moderator prepared a plan for updating the Long-RangeResearch Plan including: (1) position papers; (2) technicalforecasts; and (3) candidate projects and prioritizations.Final Rank of Problem Areas, Projects and Programs - Eachgoal area Chaimmn and Moderator reviewed the prioritizationsto compile and provide a detailed rationale for the finalranked list of projects addressing priority problem areas. Allof the given criteria were taken tito account. This proces sincluded the retision of project descriptions to avoid re-dlmdancies, the reconciliation of individual panel needs toadequately reflect ship structural research near-term andlon~tezm needs, and the time-line sequencing of projectsfrom all panels.

final output of the second workshop was the draft Long-Rangeincluding :Identification of recommended and alternate research programamade up of rational sequences of projects with a summaryof tieir relative benefits and costs.The recommended schedule for implemntatian of the selectedprograms .

Charts were developed to describe the preferred sequential acco~lish-~t of the projects within the program. Each project description containsi.nformtion regarding the data prerequisites for the project. Where suchprerequisites are minimal or nonexistent, the project can b funded aloneto suit available resources.

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A matrix of pro jec- and progrm was developed in order to providea comprehensive oveniew of the entire Program. This matrix shas where eachproject is used in the various program, the short-term scores developed bythe p r o j e c t r a t i n g s y s t e m, t i e i r o v e r a l l r a n k and tieir rank within eachgoal area. A cursory view of the matrix shws that projects generated in theresponse, mterials and fabrication goal areas are used ra re ly in programsother than in their own program area. However, the majority of the projectsfit into the master program developed for the reliability and designmethods goal aress.

Long-Range Research Needs in the Marine EnvironmentThe long-range needs in ship structural research were developed

through a hierarchy of needs from the general to the specific. These haveken classifies into several levels of need. The first level representsthe general, or overall, needs for research and develop=nt effort in themarine environment, while the second level represents the specific applica-tion of the overall needs to the problems of ship and ocean platformstructures.

The first level, or overall needs, is tie long-range needs in themarine environment which may be summarized as follows:

q Reduce marine energy consumptionq Improve energy transportationq Develop new energy sources

2. Safety and Environmentq Improve physical safe@ in the marine environmentq Develop marine systems to reduce pollutian

3. National Defense/National Securityq Develop systems to ensure tie freedom of ocesn commerceq Enhance the shipbuilding mobilization basem Reduce dependence upon foreign sources of strategic

materialsa Reduce world food shortages

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4. Commercial 13eveloymentq kvelop new marine transportation opportunitiesq Wduce cost of marine transportation

Long-Ranqe Research Needs in Ocean Structuresl%e needs at the second level are derived from the overall needs

end are the long-range research areas of need in ocean structures:Investigation of alternatives to todays shipbuilding materials --t he i r mechanical and chemical properties in marine structures,joining end fabrication techniques, optimal design concepts fortheir properties, long-term availability and cost data, mainte-nance require~nts, end useful semice lifeBehavior of todays materials in new environments and newapplicationsDesign theory aimed at optimizing fabrication techniques andse-ice performance of ship or platform structur~, consideringexpected se=ice requirementsStudy of realistic ship/ocean dynamics as they affect structuralintegrity a n d rigidity for IIISny cmfigurations of ships andplatformsStudy of damage to ships inflicted by collision, gromding, andmilitary action -- failure modes, dynamics, and design measuresto minimize damage and probability of failureKthods of accurately predicting structural performance andreliability via such methods as modeling and failure analysisR&otics and computer-aided fabrication techniquesMethods to better assure fabrication reliability in oceangoings t r u c t u r e s .

Specific Application to Structural Research ProgramsIt will be the role of fiose who sponsor research to stimulate so=

of these advances by addressing a third level of need. The needs are structurerasearoh specific and are addressed by the programs that resulted from thest* effort.

Proqram Descriptions: Research Needs for the LRRPThe programs listed here in summary form were based upan problem

areas end future requirauents identified in the workshops:

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Goal Area 1: Loadsq Non-linear Effectsq Experimental Modelsq Seaway Representationq Ice Loadsq Load CombinationsGoal Area 2: Responseq Ultimate Streng-th of Ship Structuresq Res~nses to Transient Loadsq Analytical Techniques for Predicting Structural Responsesq Structural Responses to Collision and Grounding LoadsGoal Area 3: Materialsq Marine Concrete Developmentq Mveloprnent of Composites for Marine UtilizationGOal Area 4: Fabricationq Weld Inspection llethods and Criteriaq Design for ProducticmQ Improved Welding Kthods, Equipment and Consumablesq Rational Regulatoq Requirementsq ~chnology Trsnsfer/DiffusionGoal Area 5: Reliabilityq Formulation of a Reliability Model* Data Feedback into Reliability ModelGoal ~ea 6: Desiqn Methodsq Rational Ship Design Processq Ship Vibration - Improved Par~ter Definition, Criteria andCalculation Methodsq Fatigue of Ship Structural Ele~ts, Criteria, Design Methods

and Structural Detailing

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Project ManagerJohn HopklnsonRalph E. WilliamsArthur A. SymmesCurtis S. JeffriesThomas E. CannonStephen K.H. ChuJohn A. MaloneMarjorie M. Blurtagh

APPENDIX A (Cont.)

PARTICIPANTS

IN STUDY PROJECT SR 1259

LONG-RANGE RESEARCH PLAN FORTHE SHIP STRUCTURE COMMITTEE

LRRP Project Staff

Julio GiannottiTobin R. McNattJames C. OliverDavid L. EdinbergPaul Van HaterWilliam JawishWilliam Wood

GibbsGibbsGibbsGibbsGibbsGibbsSantaSanta

& Cox, Inc.& Cox, Inc.& Cox, Inc.& Cox, Inc.& Cox, Inc.& COXt Inc.Fe CorporationFe Corporation

Giannotti & AssociatesGiannotti & AssociatesGiannotti & AssociatesGiannotti & AssociatesGiannotti & AssociatesGiannotti & AssociatesGiannotti & Associates

Guest Luncheon Speaker, June 1980 WorkshoD ConferenceMr. Peter S. Douglas

V.P. Chase Manhattan Bank NALondon, England

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AcknowledgementsThe production of this Long-Range Research Plan was made

possible through the time, energy and attention provided by thefollowing individuals in many different capacities, most on theirown time and without compensation.

Long-Range Research Program, Project sR-1259Program Advisory Committee

Mr. D.P. Courtsal, ChairmanDr. J.M. Barsom, Membe rProf. R.E. Beck, MemberProf. J.E. Goldberg, MemberMr. E.M. MacCutcheon, MemberMr. O.H. Oakley, Ex OfficioDr. J.N. Cordea, Ex OfficioMr. W.J. Lane, Ex OfficioMr. R.W. Rumke, Executive Secretary, Ship Research Committee

withLCDR T.H. Robinson, USCG, Secretary, Ship Structure CommitteeMr. A.B. Stavovy, Chairman, Ship Structure Su b c o mmi t t e eMr. W. Broadaway, USCG Contract RepresentativeCapt. R.L. Brown, USCG, LiaisonMr. T.W. Chapman, MSC LiaisonMr. R. Chiu, NAVSEA LiaisonMr. J. Gagorik, NAVSEA LiaisonMr. R.J. Giangerelli, USGS LiaisonMr. J. Gregory, USGS LiaisonMr. N.O. Hammer, FlarAd LiaisonDr. D. Liu, ABS LiaisonMr. T. Nomura, NAVSEA Contract RepresentativeMr. J.B. OBrien, NAVSEA LiaisonHr. F. Seiboldr MarAd LiaisonMr. G. Sorkin, NAVSEA LiaisonMr. D. Stein, MSC LiaisonMr. S.C. Stiansen, ABS LiaisonMr. J.P. Thomas, USCG Contract Representative

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Name

June 1980 k-orkshop Conference ParticipantsAdvanced Concepts Panel

Dr. James Lisnyk - ChairmanCapt. Charles Bishop

Mr. John Chaplin*Mr. John GregoryHr. William Jawish**Mr. William H. KummMr. Donald D. MaguraMr. Naresh ManiarDr. Donald I. MeIverMr. John OBrienHr. Harold D. RamsdenMr. William RichardsonMr. lbnald P. Roseman*Mr. Donald SteinMr. Michael Touma

Dr. Paul Kaplan - ChairmanMr. Nathan K. BalesHr. L.I?. BledsoeDr. J.P. BreslinDr. O. Hal BurnsideMr. William ClearyIX. Julio Giannotti**Hr. L.R. GlostenProf. D. HoffmanDr. Hsien Yun JanDr. E.V. LewisHr. Alexander MalakhoffDr. Owen OakleyProf. T. Francis OgilvieProf. J.R. PaullingProf. P.T. PedersonProf. Manley St. DenisDr. James StadterDr. James Steeleq Participation by Mailq * Panel Moderator

Loads Panel

OrganizationMarAdScripps Institution ofOceanographyBell AerospaceU.S. Geological SurveyGiannotti and AssociatesArctic Enterprises, Inc.ABAM Engineers, Inc.H. Rosenblatt & SonsBattelle MemorialInstituteNAVSEAGlobal Marine Development,Inc.David Taylor NSRDCHydronautics, Inc.Military Sea Lift CommandU.S. Maritime Admin.

Hydromechanics, Inc.David Taylor NSRDCNewport News Shipbuildingco.Stevens Institute ofTechnologySouthwest ResearchInstituteU.S. Coast GuardGiannotti and AssociatesL.R. Glosten, Assoc., Inc.Hoffman MaritimeConsultantsAmerican Bureau ofConsultantDavid Taylor NSRDCGulf Research andDevelopment Co.

Shipping

University of MichiganUniversity of CaliforniaTechnical University ofDenmarkConsultantApplied Physics LaboratoryConsultant

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June, 1980 Workshop Conference ParticipantsResponse Panel

Name OrganizationDr. John Dalzell - ChairmanDr. H. Norman AbramsonDr. H. Becker*Mr. Thomas P. CarrollDr. Youl-Nan ChenDr. Tom GeersMr. Michael HutherProf. N. Jones*Prof.. Xovses KaldjianMr. Roger G. KlineDr. Walter MacleanMr. H.G. Payer*Mr. F. Everett ReedDr. Paul Van Mater**Prof. William VorusHr. Charles Walburn

Stevens Inst. of TechnologySouthwest ResearchInstituteConsultantCarroll Assoc.American Bureau of ShippingIackheedBureau Veritas (France)University of Liverpool (UK)University of MichiganR.A. StearnNational Maritime ResearchCenterGermanischer Lloyd (Germany)Littleton Research &EngineeringGiannotti and AssociatesUniversity of MichiganBethlehem Steel

Materials PanelMr. John R. Belt - Chairman David Taylor NSRDCDr. B. Floyd Brown American UniversityMr. W. Gene Corley Portland Cement Assoc.Dr. John R. Davidson NASA-LangleyDr. J.G. de Oliveira MITMr. Ivo Fioriti NAVSEAHr. Olav Furness Det Norske Veritas (Nor)Mr. Richard J. Giangerelli U.S. Geological SurveyDr. C.M. Gilmore George Washington UniversityMr. R.A. Kelsey ALCOAHr. Irving L. Stern American Bureau of ShippingHr. Robert Stern AISI (Lukens Steel Co.)Mr. Arthur H. Symmes** Gibbs & Cox, Inc.

q Participation by Mailq * Pan e l Moderator

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June 1980 Workshop Conference Participants

NameFabrication Panel

Organization

Mr. John J. Garvey -Hr. Harold AckerProf. Howard BunchCdr. Lloyd C. BurgerMr. John CrookshankMr. Tom GallagherMr. Curtis Jeffries

Chairman MarAdBethlehem SteelUniversity of MichiganU.S. Coast GuardOffshore Power SystemsNAVSEAGibbs & Cox, Inc.

Mr. I Mu g l a s J. Martin ITT Research InstituteDr . Harry McHenry Nat1 Bureau of StandardsMr. John Mason Bath Iron Works Corp.Mr. Vasillios Papazoglu MITDr. Leslie W. Sandor Sun Shipbuilding

Reliability PanelName Organization

Dr. Paris Genalis - ChairmanMr. Richard J. BurkeMr. St even Chu**Dr. Gary Dau*Dr. Jeffrey T. FongDr. Joseph S. Heyman

Dr. Ambrose A. HochreinDr. Charles G. InterranteDr. Dimitri Kececioglu*Dr. Albert S. KobayashiDr. P r a mu t RawatMr. Jack SpencerMr. W. SpuymanMr. Archie WiggsDr. Jann-Nan Yang

q Participation by Mailq * Panel Moderator

47

Office of Secretary of DefeU.S. Salvage AssociationGibbs & Cox, Inc.Electric Power ResearchInstituteNat1 Bureau of StandardsNASA LangleyDaedalean Assoc.~ Inc.Nat1 Bureau of StandardsUniv. of Arizona, TucsonUniv. of WashingtonDesigners & Planners, Inc.U.S. Coast GuardTNO Inst. of MechanicalConstructions (TheNetherlands)David Taylor NSRDCGeorge Washington Univ.

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June 1980 W~rkshop Conference Participants

Design Methods PanelMr. Robert Scott - Chairman?lr.Filipo Cali*Dr. Pin-Yu ChangDr. Richard ChiuDr. J. Harvey EvansDr. Roger H. ComptonMr. Constantine FoltisMr. Alan C. McClure*Prof. William H. MunseLcdr. J.A. SanialProf. Amelio DArcangeloMr. William Wood**Hr. Paul CojeenMr. Peter WeberMr. Harald OlsenProf. Owen HughesMr. Wnald WilsonMr. John Christian

Gibbs & Cox, Inc.Cali & Assoc.Hydronautics, Inc.David Taylor NSRDCMITU.S. Naval AcademyU.S. Maritime Admin.Alan C. McClure Assoc.University of IllinoisU.S. Coast GuardUniveristy of MichiganGiannotti & AssociatesU.S. Coast GuardExxonDet Norske VeritasUniv. of New South Wales(Australia)J.J. McMullen, Inc.J.J. Henry, Inc.

q Participation by Mailq * panel Moderator

December 1980 Workshop II Participants

Workshop Chairman Workshop ModeratorDr. James Lisnyk Mr. William Jawish

. Panel ChairmenDr.Dr.Mr.Mr.Dr.Mr.

Paul KaplanJohn DalzellJohn BeltJohn GmeyParis GenalisRobert Scott

PanelsUads

Res@nseMaterialsFabricationReliability

Design Methods

Pa n e l Mo d e r a t o r sDr.Dr.Mr.Mr.Mr.Mr.

Julio GiannottiPaul Van MaterFmthur SymmesCurtis JeffriesSteven ChuWilliam Wood

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APPENDI X BKEY UNITED STATES OCEAN SYSTEMS IN A.D.2000

Seven ocean systemsto the Un i t e d S t a t e s f r o mt h e s e v e n s y s t e ms a s t h e yN a v y

were f o u n d t o b e t h e d o mi n a n t p o t e n t i a l sources of valuestructural improvement. Following are descriptions ofwere assumed to be in A.D. 2000.

The range of ship types and sizes in the U.S. Navy extends from large carriers( o f length about 1,000 ft. and displacement of about 100,000 tons) to s ma l l p a t r o la n d h a r b o r c r a f t . Co mb a t a n t s h i p s a n d c r a f t a n d , t o a l e s s e ~ d e g r e e f l e e t s u p p o rs h i p s , a r e r e q u i r e d t o b e f a s t a n d a b l e t o o p e r a t e a t h i g h speeds in rough seas.They also must be designed to resist battle damage to the degree feasible for sizeand type. These requirements strongly influence hull structure configuration,scantlings and choice of materials.

Hull configurations are, and for the foreseeable future probably will remain,primarily monohulls. However, a number of advanced concepts having special struc-tural requirements are being introduced into the fleet. Catamarans are inservice as submarine rescue ships and oceanographic ships, hydrofoil craft aspatrol crafts and gunboats, and air-cushion craft as landing craft. Hydrofoil craftand air-cushion craft require lightweight hull structure for which aluminum is thepreferred material; hydrofoil systems require high-strength steels, and the sealsor skirts on air-cushion c~aft present special demands for the development of com-pliant materials.

Improved structure can be translated into weight savings with benefits meas-urable in terms of ship size, cost, fuel economy or range, etc. , or alternatelyinto improved

In A.D.which will beOil and Gas

reliability and, important for combatants # greater damage resistance.2000 the Navycombatants.

is projected to include some 600 major ships, 450 of

The offshore oil and gas activities comprise surveying, exploring, develop-ment and production. The surveying and exploratory drilling are conducted fromplatforms ranging from conventional ship types to jack-up rigs with both semfi andfull submersibles involved. Development and production are conducted primarilyfrom fixed platforms. The operations are supported by a huge fleet of supply,catering and crew boats in ferry service between the relatively immobile platformsand shoreside depots.

The platforms are nmstly canplicated space-framed structures. Design ofthese platforms is a highly sophisticated process. Materials selection, fabri~cation techniques, construction quality control and maintenance are vital totheir survival. Of increasing importance are the severe structural and materialrequirements that must be met in the design of platforms for arctic service.

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tieswill

/-

For fixed rigs and bottom-mounted storage facilities, the special proper-of concrete may be attractive. For the floating rigs the choice of materialscontinue to be a compromise determined by construction facilities, mobility

needs and the environmental conditions at the sites.The projection for A.D. 2000 is 3500 offshore platforms with a supporting

fleet of 1800 United States vessels.Structural improvement to this fleet will mean construction and maintenance

economies along with increased reliability and safety.Transportation

The maritime fleet in the year A.D. 2000 is expected to -be daninatecl by con-tainerships., backed up by large numbers of dry-bulk carriers, LNG carriers, tankersand a few barge carriers. Traditional general cargo ships and most other ship typeswill add only a tiny fraction of the total.

The oceangoing fleet will mesh with far more numerous fleets of towboats,barges and small freighters plying the navigable rivers and the Great Lakes. Thesecraft will benefit from structural improvement, but the relative value to the U.S.is smaller so their special needs have little weight in the planning of R & D.

For the oceangoing fleet the focus is on conventional monohulls. A l l o ft h e t r a d i t i o n a l t h r u s t s t h a t have been a part of the Ship Structure CommitteeR & D program should be considered in the scope of candidates for program planning.These include research on design, materials and fabrication. ~

The oceangoing portion of the fleet is expected to canprise about 775 vesselsin foreign and domestic trade in A.D. 2000.

Benefits from structural improvement will include construction economy andfuel savings for all ships. In addition, there will be an increased carryingcapacity for those ships which are not volume limited. Probably the most importantbenefits will stem from improvements in reliability and maintainability.Recreation

Recreational craft come in a wide variety of sizes and shapes. Almost everyplatform configuration is represented. In size they range from luxury yachts dis-placing hundreds of tons down to small outboard motorboats. The small craft domi-nate the numbers.

Sales place the pleasure boatina area at over S8 billion at present, asignificant level in the national economy. There are some 14.5 million Dleasurecraft in use now and it is projected that there will be 25 million by A.D. 2000.

Fiberglass-reinforced plastic is dominant among the construction materials.However,much aluminum is used and sme wood construction continues.

Little formal research and development has been applied to the pleasure craftbut there has been much creative experimentation. Thus there is room to improve

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b u t t h e i mp r o v e me n t s wi l l b e mo d e s t a n d t h e v a l u e t o t h e Un i t e d S t a t e s will notbe large.Ocean power generation

There are several options for the generation of energy from the oceans. Theone believed to be in major use by A.D. 2000 i s o c e a n t h e r ma l energy conversion(OTEC). The projection is that there will be 25 of these plants in operation,each with a capacity of 265 megawatts (electric).

There are unique structural problems involved. The greatest is the coldwater pipe (CWP) which may be 100 ft. in diameter and 1,000 ft. to 1,500 ft.long. Other problems include deep ocean moorings and umbilical power transfercables. The hulls or platforms will be huge structures, and will be complicatedby the functional appendages.

These systems offer applications for composites, including reinforced plasticsfor the CWPS. Prestressed concrete is being considered for the platforms themselves.

Structural improvement beyond the state of the art is required to ensurethe very existence of the OTEC plants. The projection of an OTEC fleet is a pro-bability not a certainty.Fishing , aqua/mariculture

Fishing craft range from 1,000 tons downward, with half being less than fivetons in weight. The total amount of structure involved is, however, sizeablebecause it i~j expected that the United States fishing fleet will number 20,000craft in A.D. 2000. The projection calls for 3,500 craft to be under con-struction and that also represents a sizeable tonnage.

Steel will probably continue to be the material for the larger craft butcomposites, aluminum and wood will be widely used.

The value to the United States from structural improvement of these craftwill be mixed but in most cases modest.Ocean-sited industrial plants

The only offshore industrial plants forecast by A.D. 2000 are 15 floatingnuclear power plants.

These plants will involve large platforms with structural and mooring pro-blems similar to the OTEC plants. They will not involve the large CWPS but other-wise the opportunities for application of advanced structures and materials willbe similar to the OTEC units.

The value to the United States of structural improvement is somewhat specu-lative, as is the probability ofthe existence of such plants in A.D. 2000.

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APPENDIX CTECHNICAL SITUATION REVIEW

This appendix contains a summary of the highlights of the technical sit-uation from which the R & D programs must emerge. The purpose of the sectionis to outline the scope of the background material and the genesis of the LRRPprograms.

The work of the several groups that met to provide input to the LRRP isthe principal substance supporting this study. These groups consisted ofexperts from the ship research, design, construction, materials and o p e r a t i o n sc o mmu n i t i e s . The ocean platform community was only sparsely represented.

Background papers. completed by the workinq ctrouDs. consisted of oanersfor each of the six technology goal areas used by the SSC in its R & D planning.Each paper was oraanized bv a work breakdown structure (WBS) fnr the particulargoal area, and contained for each WBS category: 1) a brief description ofwork representing the state of the art, 2) a discussion of problem areas and3) a list of references. Also included was a bibliography annotated with therelevant WBS category numbers. For additional background, reference was made tothe 1 9 7 9 I n t e r n a t i o n a l S h i p S t r u c t u r e s Congress Proceedings,

Subsequently the groups prepared statements of research needs in eachgoal area. These statements covered omortunities for improvement, innovationstrategies and the rationale for emphasis among technical areas. These state-ments ended with descriptions of the proposed programs: a total of 21 c om -prising 190 projects.

This technical situation review is divided into six parts correspondingto goal areas used by the SSC in its R & D planning, i.e. loads, response,materials, fabrication, reliability and design. It summarizes the aforemen-tioned LRRP background papers and statements of research needs. The informationis abbreviated and accompained by views of the authors. Each of the six sectionsis organized as follows:

. Role of goal area

. LRRP background material scope and WBS

. Problem areasq Program rationale

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GOAL AREA 1: LOADS

All types of loads that can be experienced by ships and ocean platformsare included in this category. In some cases loads and response are not clearlyseparable so that some overlap with goal area 2Z response exists. In fact, inthe development of work parcels in the present study)the two areas were treatedtogether.

The rather extensive background paper on loads in Volume 3 of the LRRPreport is organized by the following WBS which also provides an indication ofits scope.

LOADS RESEARCH WORK BREAKDOWN STRUCTURE

1.1 STATIC LOADS1.1.1. Weight1.1.2 Still Water

1.2 CONSTRUCTION AND LAUNCHING1.2.1 Built-in & Residual Stresses1.2.2 Launching Loads1.Z.3 Docking Loads

1.3 THERHAL LOADS1.4 STEADY-STATE WAVE-INDUCED LOADS AND RELATED PHENOMENA

1.4.1 Steady-State Wave-Induced Loads1.4.2 Hydrodynamic Forces and Pressure1.4.3 Description of the Sea1.4.4 Ships Own Wave Train1.4.5 Extreme Waves

1.5 TRANSIENT DYNAMIC LOADS AND HIGH FREQUENCY LOADS DUE TO WAVESAND OTHER SOURCES1.5.1 Bottom Slamning1.5.2 Bow Flare Impact1.5.3 Green Water Impact1.5.4 Whipping1.5.5 Springing1.5.6 Wind Loads1.5.7 Explosion Loads

1.6 CARGO1.6.1 Cargo Sloshing1.6.2 Cargo Shifting

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1.6.3 Thermal Shock from Cargo Damage1.6.4 Dynamic Loads on Cargo

1.7 ICE1.8 COLLIS1ON, GROUNDING AND STRANDING LOADS

1.8.1 Collision Loads1.8.2 Grounding and Stranding Loads

1.9 PROPULSION-AND MACHINERY-INDUCED LOADS1.9.1 Propeller-Induced Loads1.9.2 Other Hull-Borne Vibration

1.10 FATIGUE LOADS1.11 LOAD CRITERIA

1.11.1 Combined Loads1.11.2 General, Naval, and Commercial Load Criteria1-.11.3 Acquisition and Analysis of Structural Service Data

1.12 MISCELLANEOUS1.12.1 Loads

The loads panel ofon Advanced Marine Vehiclesthe workshop that resu?ted in the recommended LRRp pro-

jects noted 10 broad problem areas and recommended six major rewarch prog~ams,as follows:Problem Areas

Primary Areas. Non-linear motions and extreme loads including both analytical

and experimental work. Sea representation. Combined loads. Ice loads

. Collision and grounding loadsSecondary Areas. Wake prediction for propeller forces. Expanded propeller force data base. Loads on cargo

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. Combined environmental disturbances

. Additional launch modes such as from floating platformsBased on the problem areas identified above, the panel proceeded to re-

comnend six major research programs aimed at addressing the problems identi-fied under the primary areas. These were:1.

2.

3*

4.

5.

6.

Implement a long-range fundamental research program into conceptsand methods to treat non-linear waves, motions and loads. Sucha program covers eleven different items in the loads researchWBS, and the panel estimated that the required funding would beabout $800,000 spread out. over a period of ten years.Plan and carry out model-testing programs for developing a largerdata base for analysis and correlation with dynamic and combinedloads prediction methods. It was estimated that funding on theorder of $600,000 spread over a fiveyear period would be required.Develop methodologies for combining constituent structural loadselements to establish extreme design loads and fatigue load spectra.This would encompass analytical simulations, experimental dataanalysis, probabilistic representations, etc., for both ships andoffshore structures. A funding level of $2S0,000 over a period ofthree years was estimated.Develop a design-oriented statistical representation of the seaway,including different degrees of severity, frequency of occurrenceand duration of each sea state, wave-directional characteristics,and combination of wave/wind/current effects. The panel estimatedthat a funding level of $200,000 over a period of two years wouldbe needed.Plan and implement the development of a valid method for predictingthe magnitude of ice loads. This would include development ofanalytical prediction techniques supported by model-scale tests andfull-scale measurements. It was estimated that a funding level of$300,000 over a Petiodof three years would be adequate.Carry out a comprehensive research program in the area of collisionand grounding loads. The ultimate objective is to develop practicaland valid techniques for predicting the magnitude of these loads.The analytical work must be supported by adequate experimental datacollected from large-scale structural model tests (includinglaboratory structural elements tests plus barge static and dynamictests) . A funding level of $5,000,000 over a period of five yearswas considered to be necessary.

After defining the six major program areas, the panel proceeded to preparespecific project descriptions grouped under each of the program areas. A totalof twenty-four projects were recommended.

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GOAL AREA 2: RESPONSE

Goal area two response,of qoal area one. As noted in

covers the response of structures to the loadsthe introductory remarks of qoal area one. thetwo areas overlap to some degree.

The LRRP background material on Response is also extensive. The WBS forthis qoal area is qiven below and provides an indication of its scope.

RESPONSE RESEARCH WORK BREAKDOWN STRUCTURE

2.1 RESPONSE TO STATIC LOADS2.1.1 Linear2.1.2 Non-Linear

2.2 RESPONSE TO LAUNCHING AND DOCKING LOADS2.2.1 Ships2.2.2 Offshore Structures

2.3 THERMAL2.4 RESPONSE TO STEADY-STATE DYNAMIC AND RANDOM LOADS

2.4.1 Response to2.4.2 Response to2.4.3 Response to2.4,4 Response to2,4.5 Response to

Low Frequency Wave-Induced Loads (Local and Overall)Propeller-Induce Loads (Local and Overall)Engine/Propulsor-induced Loads (Local and Overall)Wave-Induced SpringingWind-and Current-Induced Loads

2.5 RESPONSE To TRANSIENT DYNAMIC LOADS2.5.12.5.22.5.32.5.42.5.52.5.62.5.72.5.82.5.9

Response toResponse toResponse toResponse toResponse toResponse toResponse toResponse toResponse to

Bow Flare Impact (Local and Overall)Green Water (Local and Overall)Slamming (Local and Overall) and Associated WhippingCollision LoadsGrounding LoadsBlast Loads, Explosions, Underwater ShockImpact Against Floating Objects (Ice and Debris)Sloshing LoadsManeuvering Loads

2.6 FINITE ELEMENT METHOD2.7 FAILURE MECHANISHMS--FRACTURE, FATIGUE, BUCKLING, COLLAPSE, CREEP

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2.8 STRUCTURAL RESPONSE PREDICTION2.8.1 Superposition2.8.2 Probabilistic

2.9 CONCRETE STRUCTURES2.10 VIBRATION PARAMETERS, DAMPINGThe Response Panel of the LRRP Workshop noted that in the whole area of

ship structural response to loads, there was no part in which the state of theart can be considered as complete or goal achieve~.11 A nearly complete under-standing of the phenomenon of linear response to static loads and response tothermal loads exist-s. There is room for further knowledge about cyclic loadsespecially with respect to wave-induced springing and wind-and current-inducedloads. There is need for significant research in the area of transient dynamicloads including slarinning, collision and impact with ice. Also, -there isneed for further research in the area of failure mechanisms. These include:fracture, fatigue and buckling. Another area in which there is a substantialdeficiency is the knowledge of probabilistic methods as applied to structuralresponse. Finally there is a need for much more information on the variousforms of damping which influence ship vibration.

The general assessment of the state of the art is reflected in the panelsrecommendation for the programs which should receive emphasis in future researchand development efforts. These programs are listed below:

. Ultimate Strength of Ship Structures

. Responses to Transient LoadsLocal responsesGlobal responses

. Analytical Techniques for PredictingStructural Responses

. Structural Responses to Collision andGrounding Loads

In addition to the proposed programs, some additional projects of secondarypriority were also proposed:

. A Survey of Available Finite-Element ProgramsApplicable for Ship Structures

. Structural Response to External Blasts

. Structural Response to Internal ExplosionsAltlmugh some projects directed at offshore platforms were proposed, con-

sideration of the problems preculiar to these structures (particularly withregard to bottom-mounted platforms) was far from complete.

Other gaps noted in the Response programs are consideration of the transversestrength of catamarans and SWATH, the strength of submarine and submersible pres-sure hulls and the strength of other elem=nts subject to deep submergence pressure.While these areas are considered imprtant technically, the national importanceratings likely to be attached to SSC work parcels to support them for cornnercialapplications probably would be low.

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GOAL AREA 3: MATERIALS

The areas of materials and fabrication together are closely allied tothe large-scale construction which is characteristic of marine structures.The needs of the next two decades involve offshore systems to recover oil andminerals at increasing depths, transportation systems of higher speed andgreater economy and a grcwing Navy of increasing effectiveness. Material andfabrication developments will be critical to meeting these needs.

The fundamental properties required of materials to meet marine applica-tions relate to combinations of static and fatigue strength, notch toughness,and corrosion resistance. Advances in the design of structures intended toprovide improved performance in projected marine applications can be aided byimproving the critical properties of the materials in these structures. Thushigher strength steels can save weight in floating structures or extend therange of depths for platforms and ocean bottom systems. Improved reinforcedor prestressed concrete can permit construction economies and enhance resistanceto marine life attack. Materials may be combined in new ways to obtain tailor-made properties for particular components of structures, e.g. corrosion-resist-ant and anti-fouling hull surfaces, wear-resistant foundations and notch-toughmembers that are dynamically loaded, all to enhance the performance of thesystem.

The WBS for materials, which follows, is inferred from the content of thebackground paper narrative:

MATERIALS RESEARCH WORK BREAKDOWN STRUCTURE

3.1 STEEL3.1.1 Steel - Material Properties/Performance3.1.2 Steel - Fracture/Fatigue

3.2 ALUMINUMfilTANIUH3-2.1 Aluminum - Material Properties/Performance3.2.2 Al~inum - Fracture/Fatigue

3=3 REINFORCED PLASTIC

3.3.1 Reinforced Plastic Composites - Material Properties/Performance3.3.2 Reinforced Plastic Co mp o s i t e s - Fracture/Fatigue3.3.3 Reinforced Plastic Compos

3.4 cONCRETE3.4.1 Concrete Material - Mater

tes - Construction ~nd Repair

a-l Properties/Performance

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3.4.2 Concrete - Fatigue/Fracture3.4.3 Concrete - Construction/Reps ir3.3.4 Ferro - Cement

The problem areas and program rationale for materials is in the PromisinTechnology section of the main body of this r e p o r t . Se e p a g e 1 4 .

.-

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GOAL AREA 4: FABRICATION

The improvements that can be developed in the fabrication field haveacross-the-board significance to the gamut of platform configurations. First,in production design structural details can be chosen to improve the qualityand economy of welding assembly. Second, automatic controls, process improve-ments, and robotics can raise productions rates in welding. Third, recentstrides in inspection methods for weldments can assure that imperfections canbe held to a chosen size, and fourth, analytical methods can be refined tospecify quality control levels on the basis of fitness for purpose rather thanon arbitrary and often overconservative grounds. Attainment of many of thesegoals can be facilitated and speeded by appropriate technology transfer fromother industries and countries.

FABRICATION RESEARCH WORK BREAKDOWN STRUCTURE

4.1 DESIGN/Production INTEGRATION4.2 PRODUCTION MANAGEMENT

4.2.1 Planning and Production Control4.2.2 Accuracy Control

4.3 COMPUTER-AIDED DESIGN/COHPUTER-AIDED MANUFACTIJRE4.4 WELDING AND ALLIED PROCESSES

4.4.1 Welding4.4.2 Welding Support Equipment4.4.3 Inspection of Welds

4.5 PRODUCTION PROCESS4.5.1 Material Handling and Load Moving SystemsJt.5.2 Surface Preparation4.5.3 Cutting Methods4.5.4 Forming Processes

4.6 NON HETALS4.6.1 Concrete4.6.2 Fiber-Reinforced P l a s t i c4 . 6 . 3 Wo o d - L ami n a t e s

The problem areas and program rationale for fabrication are in the promisinTechnology section of the main body of this report. See page 14.

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GOAL AREA 5 RELIABILITY

The concepts of reliability and risk underlie all structural design andanalysis. They constitute the ultimate mode of expression for structural per-formance and are essential to quantitative estimating of maintenance costs,system efficiency and safety.

Reliability analysis is not another method of predicting structural re-sponse, even though, using the techniques developed, the response of the struc-ture is predicted in an appropriate way. Further, reliability analysis is notcontinuing everything were doing already, except re-formulating it in probabi-listic terms. Rather is is an all-encompassing ship structure design method-ology which has as its end result not only a structure or a prediction of itsresponse given certain inputs; but, and this is its distinguishing feature, italso addresses and results in a quantitative measure of uncertainty which thedesigner, the owner, or the classification society may accept or not. It is aneffort to determine how much one is not sure about. Obviously, it is philoso-phically impossible to reach that state because the inputs to this uncertain-ties analysis are, to an extent, uncertain themselves. It is important torecognize this because reliability analysis has often been touted as a methodwhich largely eliminates engineering judgement calls and totally eliminatesthe factor of safety. Not SO. It only guides the engineer twards makingthose judgments very consciously, and on smaller ranges of the variables, byforcing a recognition of the uncertainties at each level of the design process.

The LRRP report contains an elaborate statement on the subject of reliabi-1 ity. It commences with a comprehensive work breakdown structure as follows:

RELIABILITY RESEARCH WORK BREAKDOWN STRUCTURE

7.1 OVERVIEW OF STRUCTURAL SAFETY7.2 SUCCESSFUL APPLICATION IN OTHER FIELDS7.3 DEFINITIONS FOR RELIABILITY7.4 FAILURE MODES AND HECHANISHS7.5 FACTORS AFFECTING STRUCTURAL RELIABILITY IN SHIPS

7.5.17.5.27.5.37.5.4;.;.;7:5:77.5.87.5.97.5.10

Load CriteriaStress and Strength CriteriaFatigue, Fracture and CorrosionMethods of AnalysisDesign Methods and Design DetailsFabrication and Welding ProcessesData Sources and Use of InformationScheduled Maintenance and Its Effects on ReliabilityQualityAssurance/Quality Control (QA/QC)Cost Economics and Profitability

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7.5.11 Collision and Other Failures7.5.12 Classification Societies

7.6 RELIABILITY MODELS AND ASSESSMENTS IN SHIP STRUCTURES7.7 INSPECTION TECHNIQUES7 . 8 AVA I L ABL E MAT ERI AL S7 . 9 SPECI AL ST RUCT URES

7.9.1 Offshore Platforms7.9.2 Advanced Surface Ships/Fast Craft Submersibles7.9.3 Bow a n d Stern Structures7.9.4 LNG/LPG Carriers7.9.5 Nuclear Powered Ships7.9.6 Coastal S t r u c t u r e s7 . 9 . 7 I c e S t r e n g t h e n i n g7 . 9 . 8 Ma c h i n e r y F o u n d a t i o n

Each part of the work breakdown structure has been developed with a sub-stantial narrative statement describing the state of the art in reliability ansupporting these statements with references. In many cases a statement of pro-blems is included.

We are not going to start designing ship structures using the reliabilitymethod tommorrow morning or on January 1, 1987. Nor are we going to totallyabandon deterministic approaches at sane specific time, or when the reliabilitymethod reaches an a priori determined level of maturity. Rather, both methodswill co-exist, and in fact do co-exi s t , each offering its unique feature to thproduction of better structures. Several papers have been published addressingsemi-probabi 1 istic solutions to specific problems. This trend will probablycontinue, with reliability methodology growing stronger as its yet unexploredand untapped resources become recognized and are reduced from academic intri-cacies to practical tools. To sustain and reap the benefits of this evolution,two tasks must be fostered: (a) sponsor and guide the research as proposed bthe Reliability Panel and modified by other experts and the wisdom of time and(b) effectively transfer the results of the research to the practicingnavalarchitect.

The programs developed by the Reliability Panel are:No, E5!EE5 A F o r mu l a t i o n o f a Re l i a b i l i t y Model5B Data Feedback Into a Reliability Hodel

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Statistically significant casualty data are essentially unavailable forships. In one case, in the history of the world, 2700 liberty ships were built.Many of these were similar. But, even fcwstatistical purposes with the liber-ties, more than a 1.,000 must be cast out because they were converted or werebasically different to begin with. The statistical sample, thus, was reducedto 1700 and this sample was subjected to competent professional statisticalanalysis. Probably the situation will never be repeated and thus the casualtyrecords of the future must come from sister ships, groups of two, three andfour ships.. The statistical techniques for most reliability analysis andforecasting are based on aircraft and automobile experience. The post-mortemrecords on aircraft come. from hundreds of very similar units and on automobilesfrom tens of thousands of essentially identical units. Atte~ting to adaptsimilar statistical techniques to ships is a frustrating endeavor.

Reliability has assumed the stature of a goal area in the SSC program.This tends to make reliability an end in itself , and due to the breadth ofapplication of the concept, it promotes an overlay of duplicating projects.

The SSC probably should &onsider retaining reliability as the ultimateconcept for design but eliminate the promotional distortion occurring becausethe subject has been made a goal area. instead it would be wiser to fosterpromising reliability studies in c~petition with alternative approaches foreach branch of the ship design activity. This would promote the reliabilityconcept as the ultimate approach but cause it to assume a reasonable and appro-priate role in each design area where it can be used.

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GOAL AREA 6: DESIGN

in developing this study, the authors tended to be more rigid in theirinterpretation of what would be considered design methods. We limited thisgoal area to ship structure performance goals, objectives and criteria includ-ing design techniques, procedures and their sequencing. We included the neces-sary synthesis and coordination among all goal areas and with this the data bankmanagement and informational input including such things as casualty reports.Many projects included by the LRRP were distributed to other goal areas becausethey dealt with investigation and experimentation leading toward the validationof theories relating to physical behavior or system performance; these l a t t e rma t t e r s b e i n g more appropriately under the loads, response, materials and fabri-cation goal areas.

The basic issues or goals developed by the Design Methods Panel were:1. To convert state of the art knowledge into design-oriented

tools.2. To promote communications between owners, builders and

designers.3. To develop design tools necessary to accept new, uniquestructural materials.4. To develop design tools applicable to unique ship types.5. To transfer offshore industry knowledge into a structural

design community.6. To insure relevant academic experience in current curricula

covering structures.There is one basic goal which encompasses all of.the above, the develop-

me n t of t h e so-called rational design method.lFor the purposes of this post-workshop analysis and research program

development, it will be assumed that the major umbrella program resulting fromthe Design Methods Workshop is the formulation and development of a rationaland explicit design method based on load prediction, material selection, responseanalysis, definition of design constraints, selection of a measure of quality,design optimization and appraisal of safety.

The state of the art description pertaining to design methods is compre-hensive and starts with a work breakdown structure followd by an amplificationof each including background and citing problems. Perhaps the most importantproblem mentioned was in effect the state of the art/in converting the re-searchers state of the art knowledge into user-oriented tools is sorely lagging.The latter is often referred to as the state of the practice.

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DESIGN METHODS RESEARCH WORK BREAKDOWN STRUCTURE

-6.1 MARINE STRUCTURAL DESIGN--GENERAL6 . 2 STRUCTURAL sy5TEMANALYsls (DEMANO)

6.2.1 Environment6.2.2 Loads and R e s p o n s e

6.2.1.1 Still Water Loads6.2,1.2. Low Frequency Loads6.2.1.3 High Frequency Loads6,2.1.4 Other Loads6.2.1.5 Combination of Loads

6,2.3 Methods of Analysis6 . 3 ST RUCT URAL DES I GN CRITERIA (Capability)

6.3.1 Strength Criteria6.3.1.1 Materials and Fabrication6.3.1.2 Limit States6.3.1.3 Fatigue Strength

6 . 3 , 2 E v a l u a t i o n o f - De ma n d v s . Ca p a b i l i t y6.4 DESIGN OBJECTIVES

6.4.1 Reliability6.4.2 Production6.4.3 Operation6.4.4 Optimization6.5.5 Computational Methods

In spite of the p.ka to aim at a super rational design method, the workbreakdown structure generates problems in acconsnodating important areas requir-ing research. These include how to handle corrosion, the need for maintain-abi l i ty and inspectability, the question of monitoring in service, lifetimecost and the whole area of gathering and handling information in support ofdesign methods.

The groups came up with -eighteen program areas as follows:. Design Methods for Non-Metallic Haterials. Analysis of Existing Ships to Calibrate New Design Methods

(Hindcast ing)q Standardization of S-N Data (Fatigue). Integration of Loads Data with Appropriate Design Toolsq Methods of Superimposing Design Loads. Tools for Dynamic Analysis of Structural Elenents

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q

q

Applicability of Fracture Mechanics to DesignDesign tools for Collision Damage AnalysisIce Loading CriteriaCommercial Submarine Design MethodsFatigue Design, Details CriteriaConsideration of Residual Stresses in DesignNeed for Clearing House on Computer-Aided Design ToolsFurther Development of Existing Computer-Aided Design ToolsConsideration of Corrosion in DesignHull Deflection CriteriaLateral, Torsional Design MethodsFeedback of Casualty Data into Design

These eighteen program areas led to the naming of thirty-four projectsfrom which the work parcels of this study were derived.

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APPENDIX DWORK PARCELS

The work parcels described here consist of mutually supporting setsof R & D tasks which are essential canponents for achieving specified goals.

Appendix D is in two parts. The first part is a list of work parceltitles and the second part contains brief descriptions of each work parcel.Bcith parts are arranged by subject. The broad goal areas are essentiallythe traditional categories of the Ship Structure Committee program; loads,response, materials, fabrication, reliability and design. Subordinate subjectheadings have been selected to suit the work parcel content.

APPENDIX D - PART ONELIST OF WORK PARCELS

Loads and Response Goal Areas

Seaway descriptionLO1 Directional Sea Spectra

Rigid body responseL02 Method for Predicting Loads Induced by Large Non-Linear Head SeasL03 Method for Predicting Moored Vessel Motions and Loads

Elastic response - wave bendingL04 Combined Bending and Torsion Loads on ShipsL05 Static Torsion of Ships Hull GirderL06 Wave-Induced Springing Response

Elastic response - wave impactL07 Slamming and Bow Flare Impact, Hull Girder ResponseL08 Slanxning and Bow Flare impact, Local Response

Elastic response - topside loadsL09 Hull Girder Response to Green Water on (leekL1O Local Response to Green Water on Deck

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Failure mechanismsLll Combination of Low and High Frequency LoadsL12 Experimental Determination of a Family of S-N Curves for Typical

Ships Structural DetailsL13 Fatigue Parameter EvaluationL14 Hull Girder Collapse, Analysis of Torsion and Torsion-Buckling ModesL15 Hull Girder Collapse, Buckling and Plastic balesL16 Shakedown Analysis of Hull GirdersL17 Hull Girder Failure, Analysis of Fracture Mode

Cargo loadsL18 Local Response to L

Ice loadsL19 Ice Loads on

Collision and groundinq

quid Cargo Sloshing Impact

Ships and Platforms

L20 Ship Collisions, Analysis of Hydrodynamic ForcesL21 Ship Collisions, Large-Scale ExperimentsL22 Ship Grounding.Loads, Analysis and ExperimentL23 Ship Collisions, Hull Structural Elements, Model Test Program

VibrationL24 Analytical Study of Hull Pressures Induced by Intermittent Propeller

CavitationL25 Analytical Study of Wake, Hull Shape and Propeller-Induced ForcesL26 Study of Wake Harmonics, Model and Full-Scale MeasurementsL27 Study of Wake Harmonics Using Instrumented PropellerL28 Correlation of Calculated. and Measured Propeller Blade PressuresL29 Added Mass of Locally Vibrating StructureL30 Ship Vibration Response, Full-Scale MeasurementsL31 Validation of Methods for Predicting Higher Mode Frequencies

Material Goal Area

Concrete damage and repairHO1 Damage Assessment in ConcreteM02 Guidelines for Repair of Marine Concrete Structures

Improvements in reinforced concreteM03 Evaluation of Alternative Reinforcements in Concrete

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M04 Develop High Strength-to-Weight ConcreteH05 Fatigue in Marine Concrete StructuresM06 Corrosion in Concrete and Its Inhibition

Crack arrest technologyH07 Crack Arrest in MetalsM08 Ductile Fracture Mechanics for Ship Steels

Copper - nickel sheathingM09 Joining Copper-Nickel to SteelM1O Effect of Sheathing on Skin Friction

Fabrication Goal Area

FO1 Fitness for Service Criteria,F02 Weld Inspection and Repair StandardsF03 Ultrasonic InspectionF04 Nondestructive On-Line Inspection Technique

CAO/CAtl for fabrication of platforms and shipsF05 CAD/CAM Data Base FormatsF06 Outfit Design System Specification

Production control

F07 Review of lndustriaJ Engineering ApplicationsF08 Shipyard Production ControlDesign for production

F09 Design Details to Aid ProductionF1O Design-for-Production Manual

Weldinq developmentFll Welding Robots and Adaptive ControlsF12 Improved Welding Methods and Consumables

Reliability Goal Area

RO1 Reliability AnalysisR02 Reliability of Structures and Elements

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.. R03 Structural FailureR04 Effect of Maintenance on ReliabilityR05 Guidelines for Scheduled Inspection and Maintenance

Design Goal Area

Gene ra 1001 Structural Performance, Monitoring in Service002 Reliability of StructureD03 Casualty Reporting004 Computer-Program Clearing HouseD05 Future Needs for Computer-Aided Design (CAD) Methods006 Finite-Elemnt Methods (FEM) Computer-Program Survey

Structural system analysis - low frequency loadsD07 Wave Data for DesignD08 Cargo/Structure Interaction

Structural system analys;s - high frequency loadsD09 Impact on Structural Elements, Analysis and CriteriaD1O Predicting Wave-Impact LoadsDll Predicting Propeller-Induced Forces012 Vibrations Prediction Modeling-Techniques Improvement

Structural system analysis - methods of analysis

D13 Designing for CorrosionD14 Designing Arctic Submarine Structure, Methods and CriteriaD15 Viability of Concrete Hulls016 Designing Concrete Structure, Methods and Criteria017 Transverse-Strength Analysis018 Superimposing Design Loads019 Rational Ship Design

Structural system analysis - other loads020 Designing Against Fatigue021 Collisions and Grounding

Structural design criteriaD22 Hull Girder Deflection CriteriaD23 Ice Loading Criteria

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Desiqn objectives024 Optimization Anmng Design CriteriaD25 Designing for Inspectability and Maintainability

Design processD26 Designing to Minimize Green Water LoadsD27 Vibration Studies Scheduling in the Design Cycle

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APPENDIX D - PART TWODESCRIPTION OF WORK PARCELS

Loads and Response Goal Areas

LO1 DIRECTIONAL SEA SPECTRAObjective: A plan for routine measurement of seaways to obtaindirectional spectra.

(a):Evaluation/Comparison of Procedures for Measuring Direc-tional Characteristics of SeawaysMethod: Evaluation of current state of the art methods ofmeasuring seaways to extract directional data. Employingdirect comparison of data from sources such as radar,s t e r e o p h o t o g r a p h y , wa v e g a u g e a r r a y s , h i n d c a s t i n g .

(b): Plan for Routine Measurement of Seaways to Obtain Direc-tional SpectraMethod: Assess present techniques, evaluate error sources;recommend techniques for obtaining measurements; recom-mend methods for reducing, presenting and storing data;estimate costs.

Cost/Duration: $130K, 2 years

L02 METHOD FOR PREDICTING LOADS INDUCED BY LARGE NON-LINEAR HEAD SEASObjective: A method for predicting wave-induced loads on a ship inlarge non-linear form head seas.Flethod: Theoretical development beyond present linear models,accounting for effect of ship passage thru waves, such as: deformationof wave, change in hull water plane area with time, ships own wavetrain, etc.Cost/Duration: $165K, 2 years

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.., L03

L04

L05

L06

f4ETHOD FOR PREDObjective: The

CTING MOORE D V ES SE L MOTIONS AND LOADStitled method

Met hod: Analysis of motions and loads in extreme seas (ultimatesurvival case) supported by model tests and full-scale measurements,considering forces due to waves, wave drift, currents and wind onmoored vessels or platforms, particularly those having bluff hullforms.Cost/Duration: $160K, 1 year

COMBINED BENDING AND TORSION LOADS ON SHIPSHULL GIRDERObjective: Verification of existing theoryMethod: Hydrodynamic model tests using articulated models instrumentedto measure motions, pressures, bending moments (2 axes), torsion}etc.Cost/Duration: $200K, 1+ years

STATIC TORSION OF SHIPS HULL GIRDERObjective: Improved analytic/numerical methods to predict deformationand stress distribution for ore carriers, container shipszetc. undertorsion.Method: Full-scale static torsion test of suitable ship and compar-ison with FEM analysis.Cost/Duration: $500k, 3 years

WAVE-INDUCED SPRINGING RESPONSEObjective:

(a) :Improved methods of prediction of springing response.

Effect of Hull Shape on Wave-Induced SpringingMethod: Analytical study to evaluate magnitude of varia-tions in added mass, damping, buoyancy loads related torealistic variations in bow and stern shape and the corres-ponding springing response.

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(b) : Method for Prediction of Springing ....6-Met hod: Investigate the wave-induced excitation acd hydro-dynamic damping associated with springing. Analytical studyutilizing data from full-scale springing measurements onthe S. J. CORT, U. of Michigan model test work and the resultsof component a to provide basis for improved predictivemethods.

Cost/Duration: $160K, 2 years

L07 SLAMMING AND BOW FLARE IMPACT,Objective: Improved method ofinduced bow impact loads.

HULL GIRDER RESPONSEpredicting hull girder response to wave-

(a ) :

(b) :

Bow Impact Loads - Model Test and Correlation with TheoryMet hod: Tests on articulated hydrodynamic models in lockedand flexible modes and correlation with available theoryfor slamming and bow flare impact loads. .Method of Calculating Hull Girder Response to BW ImpactLoads.Method: Development of analytical/computational model forthe titled problem and verification using available modeland full-scale data including the results of component a above.

Cost/Duration: $400K, 3 years

L08 SLAMMING AND BOW FLARE IMPACT, LOCAL RESPONSEObjective; Development and verification of improved methods of pre-dicting the response of local bottom and bw flare structure to wave-induced impact loads.

(a):

(b):

Slamming and Bow Flare Impact, Local Response, Full-ScaleMeasurementsHet hod: Full-scale experimental program to measure localresponse of plating and plate-stiffener combinations.Associated local dynamic pressures and overall rigid bodymotions should also be measured.Slainning and BW Flare Impact, Local Response, Model Testsand Analytical Model DevelopmentHet hod: Analytical development of an elasto-plastic model.Validation by numerical calculations c~pared with structural

.

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model tests at large enough scale to permit accuratemodelling of details (f scale or greater), and L08results if available.

Cost/Duration: $320K, 3 years

L09 HULL GIRDER RESPONSE TO GREEN WATER ON DECKObjective: Analytical/computational method for response of hull girderassociated with shipping of green water.Method: Development of elastic model for title problem and validation,if feasible, with full-scale data. Results from L07 may provideframework.Cost/Duration: $150K, 2 years

L1O LOCAL RESPONSE TO GREEN WATER ON DECKObjective: Analytical/computational method for treatment of localstructural response to green water topside loads.Method: Develop an elasto-plastic model ling method for the title problemCost/Duration: $150K, 2 years

Lll COMBINATION OF LOW-AND HIGH-FREQUENCY LOADSObjective: Analytical methods for titled problem aimed at (i) estimtingextreme values and (ii) fatigue load spectra.Method: (i) Determine phasing of low-and high-frequency loads basedon full-scale data and theoretical predictions. Determine correlationcoefficients for combining maximum values of low and high frequencyranges of long-term predictions. Include consideration of combinedprimary, secondary and tertiary stresses. (ii) Similarly developimproved method for producing load or stress spectra suitable foranalysis of fatigue as follow-on to existing SSC project (SR-1254).Cost/Duration: $230K, 3 years

LIZ EXPERIMENTAL DETERMINATION OF A FAMILY OF S-N CURVES FOR TYPICAL SHIPSSTRUCTURAL DETAILSObjective: The titled S-N curves.

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Method: Similar to American Welding Society curves and w.rk by off-shore industry on tubular joints. Effects of overtrain and endur-ance limit to be considered in design of tests. This work would providelink between two existing SSC projects on fatigue dealing with method-ology and load spectrum, and continue experimental wrk started underSSC sponsorship.Cost/Duration: $400K, 3 years

L 1 3 F AT I GUE PARAMET ER EVAL UAT I ONObjective: Determination of the effects and importance of such vari-ables as mean stress, material properties, residual stresses and thermalstresses in predicting fatigue performance of welded structural details.Met hod: Using results of L12, hindcast effects of variables enumer-ated above on actual details.Cost/Duration: $300K, 3 - 5 yearsPrerequisites: Appendage to L12.

L14 HULL GIRDER COLLAPSE, ANA~YSIS OF TORSION AND TORSION BUCKLING MODESObjective: Determine load carrying capacity of shipls hull girderin modes of torsional collapse and torsion combined with compressivebuckling. Possible coupling with other failure modes also to beconsidered.Met hod: Analytical study. Follow-on to SSC 299Cost/Duration: $68K, 1 year

L15 , HULL GIRDER COLLAPSE, BUCKLING ANO PLASTIC WDESObjective: Experimental verification and calibration of analyticalmethods treating hull girder failure by a combination of bucklingand plastic deformation.Method: Work to proceed in two stages (i) testing of small modelswhere analytical solutions exist, (ii) testing of larger scale nmdelsresembling actual ship structures.Cost/Duration: $250K, 1+ years

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L16 SHAKEDOWN ANALYSIS OF HULL GIRDERSObjective: Further clarify the role of shakedown in the overallfailure mechanism of hull girders and develop new or improvedmethods for ship structures.Met hod: Analytical studyCost/Duration: $80K, 1 year

L17 HULL GIRDER FAILURE, ANALYSIS OF FRACTURE MODEObjective: To determine the strength of ships hull girder consideringpresence of fatigue crack(s).Hethod: Analytical study of failure under single ultimate mbmentapplicaticm for cracks of varying severity. Recommendations forfollw-on experimental work.Cost/Duration: $80K, 1 year

LIB LOCAL RESPONSE TO LIQUID CARGO SLOSHING IMPACTObjective: Analytical/computational method for cargo tank structure,especially for LNG chemical carriers.Method: An elasto-plastic modelling method is envisioned, to bevalidated by experimental data at approximately 1/10 scale.Cost/Duration: $175K, 2 Years

L19 ICE LOADS ON SHIPS AND PLATFORMSObjective: Method of estimating magnitude of time history of iceloads on moving vessels and fixed platforms.

(a): Full-Scale Ice LoadMeasurementsHethod : Review existing data. Evaluate loads imposed onships hulls and platforms by ice. Establish operatingcriteria (situations). Conduct ice strength measurements.Conduct ice strength load/impact studies.

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(b) :

(c) :

Methodology for Predicting Ice LoadsMethod: Analytical study of titled problem. Utilizedata from L19.

Ice Load Simulation, tlodel TestingMethod: Design and conduct model experiments and correlateresults with full-scale measurements and analytical pre-dictions.

Cost/Duration: $630K, 3 years

L20 SHIP COLLISIONS, ANALYSIS OF HYDRODYNAMIC FORCESObjective: Determine hydrodynamic forces involved in ship collisions.Method: Analytical and experimental study. Tests envisioned for 3mo d e l s , v a r i o u s d r a f t s , speeds and angles of impact. Results to bein parametric form for use in analysis or design studies.Cost/Duration: $150K, 1 year

L21 SHIP COLLISIONS, LARGE-SCALE EXPERIMENTSObjective: To validate simple and complex methods of design andanalysis for low speed ship collisions by acquiring loading and damagedata.Me t h o d : L a r g e - Or f u ] ] - s c a l e shiD collision experiments are estimatedt o cos t $3000K or more. The USCG has plans to carry out such experi-ments (See USCG Report CG-D-21-80, March 1980 Vessel Collision DamageResistance - Development of Preliminary Test Plan for Large/Full-ScaleVessel Collision Tests). The scope of this work parcel is to monitorand evaluate the USCG project if it is undertaken.Cost/Duration: $30K, 1 year.Prerequisite: USCG collision project

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L22 SHIP GROUNDING LOADS, ANALYSIS AND EXPERIMENTObjective: To provide an analytical tool for predicting grounding loadas a function of ship bottcm structure, sea bottom soil or obstaclecharacteristics and ship speed.Met hod: Develop analytical simulation of grounding phenomenon includingconsideration of ship geometry, ship/soil interaction and soil/bottom

mechanical properties. Design and test a procedure to measure groundingloads as a function of ship/soil characteristics.Cost/Duration: $200K, 2 years

L23 SHIP COLLISIONS, HULL STRUCTURAL ELEMENTS, MODEL TEST PROGRAMObjective: To provide an experimental data base for use in collisionsand damage - resistance analysis.Method: Conduct laboratory tests of ship structural elements

Models shoul~ !~)nosing static loading (b) using dynamic loading.smaller than 4 scale and incorporate typical ship steel plates andshapes fabricated using typical shipyard practice, and embody variousconfigurations of plates, stiffened panels and end connections.Cost/Duration: $275K, 1+ years

L24 ANAL~lCAL STUDY OF HULL PRESSURES INDUCED BY INTERMITTENT PROPELLERCAVITATIONObjective: To determine the accuracy of Massachusetts institute ofTechnology-Stevens Institute of Technology (MIT-SIT) program for suchpressures compared with measurements made at the Swedish Marine Re-search Center (SSPA), Goteborg, Sweden.Methods: Programs exist but must be exercised. Data provided bySSPA has been compared with results of MIT-SIT programs. Furthervalidation using data from other sources is required. Note ongoingUSN work in this area.Cost/Duration: $40K, 1 year

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/,/ L25 ANALYTICAL STUDY OF WAKE, HULL SHAPE AND PROPELLER-INDUCED FORCES/ Objective:/ Determine the influence of stern g e o me t r y o n wa k e p a t t e r n a n d h o w wa k e a f f e c t s p r o p e l l e r l o a d s a n d h u l l p r e s s u r e s .

Met hod: Analytical study using existing wake data and existing pro-grams for calculating hull forces with and without cavitation. Shouldbe coordinated with ongoing USN efforts.Cost/Duration: $75K, l+ yea~s

L26 STUDY OF WAKEHARMONICS, MODEL AND FULL-SCALE MEASUREMENTSObjective: Determine the effects of scale and hull geometry on har-nmnics of wake.Method: t40del and full-scale measurements of wake for 3 ships usinglaser doppler velocity meter techniques. Compare results to determineeffects of Reynolds number and hull geometry. Measure hull surfacepressures. Derive influence of propeller in nominal wake field.Cost/Duration: $40K, 2 years

L27 STUDY O.F WAKE HARMONICS USING INSTRUMENTED PROPELLERObjective: Increase understanding of the spatial harmonics of shipswake using pressure gauges along the span of one blade of a propellerin both nmdel and full scale.Method: (see objective) Tests of model corresponding to fulpropeller to be instrumented should be successfully completedto denmnstrate one-to-one relationship between pressure gaugeand each wake harmonic.

-scalefirstoutput

Cost/Duration:

L28 CORRELATION OFObjective: To

$250K, 2 years

CALCULATED AND MEASURED PROPELLER BLADE PRESSURESvalidate existing unsteady blade-pressure program.

Method: Data from German large-scale tests in air are available.These to be compared with calculated values using existing theory andcomputer program.Cost/Duration: $50K, 1 year

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LZ8 (Cont.)References:

E. A. Weitendorf. Cavitation and InfAmplitudes.Systems. Det

. K. Kienappel.Rotvienden.

uence on Induced Hull PressuSymposium on Hydrodynamics of Ship and Offshore PropuNordske Ventas, Oslo, Norway 1977.Unterschung zer Messung Interstationaerer Drucke

AVA report DL F - F B - 7 7 - 4 3 , 1 9 7 7 .

L 2 9 ADDED MASS OF LOCALLY VIBRATING STRUCTURESObjective: To obtain data on added mass coefficients applicable tovibratory behavior of local structure such as bulkheads, web framesand local bottom structure.

Method: Problem could be approached experimentally or analytically.If analytically, it should be substantiated by a small experimentalprogram. Should consider cases with fluid on one or both sides ofthe vibrating structure.Cost/ Duration: $1OOK, 2 years.

L30 SHIP VIBRATION RESPONSE, FULL-SCALE MEASUREMENTSObjective: To improve the representation of damping in hull girdervibration calculations.Method: Full-scale testing (shaker). Will require rental of equip-ment and loan of or access to, several ships. To consider structuralhydrodynamic and cargo influences on total damping. Tests to be de-signed to allow extraction of definitive information on naturalfrequencies, modeCost/Duration:

shapes and damping.$500K, 3 years

L31 VALIDATION OF HETHODS FOR PREDICTING HIGHER MODE FREQUENCIES

Objective: Either validate or provide guidance for extending FEMmethodology for the undamped case.Method: Correlation of computer analysis with full-scale data fromL30.Cost/Duration: $12!jK, 14 yearPrerequisite: L3~

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/Materials Goal Area

Ho 1 DAMAGE ASSESSMENT IN CONC.RETEObjective: To improve NDT e q u i p me n t a n d p r o c e d u r e s for evaluating theextent of damage in concrete, investigate damage mechanisms, andprepare rational guidelines for damage assessment.Method: Experimental developmentwith existing techniques and examCostlDuration: $400K, 5 years

of equipment and procedures startingnation of potential of new technology.

M02 GUIDELINES FOR REPAIR OF MARINE CONCRETE STRUCTURESObjective: To provide standardized repair techniques that reduce timand cost, and prepare a handbook.Hethod: Experimental development of standardized repamatched to nature of damage using existing technology.Cost/Duration: $125K, 2 years

M03 EVALUATION OF ALTERNATIVE REINFORCEMENTS IN CONCRETE

r techniques

Objective: To provide alternate methods of reinforcing concrete toimprove load bearing and impact properties.Met hod: Experimental testing of material properties of concretereinforced with fibers, ferrocement, etc.Cost/Duration: $600K, 5 years

M04 DEVELOPMENT OF HIGH STRENGTH-TO-WEIGHT CONCRETEObjective: To provide high strength, lightweight concrete that iscompetitive with steel in useful load-to-total-weight ratio.Method: Experimental study of properties of candidate materials andnew materials with strength-weight ratios similar t o steel.Cost/Duration: $350K, 1* years.

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M05 FATIGUE IN MARINE CONCRETE STRUCTURES

.,:,

Objective: To identify fatigue problem areas with emphasis on fatiguein shear and in reinforcement.Method: Experimental investigation of fatigue in prestressingtendons, fibers, and re-bars including a n a t u r a l Se a wa , t e r e n v i r o n me n t .Cost/Duration: $ 1 , 5 0 0 K , 3 y e a r sPrerequisite: M04

M0 6 CORROSION IN CONCRETE AND iTS INHIBITIONObjective: To identify potential corrosion problems and developcorrosion protection methods, resulting in corrosion control guide-line manual.Method: Literature review, investigation of corrosion inhibitors andtheir requirements.Cost/Duration: $200K, 1 year

M07 CRACK ARREST IN METALSObjective: To develop damage-tolerant structural configurations thatarrest unstably running cracks.Method: Evaluate effects of large inertial loads on crack arrest bystringers and plates, and conduct large-scale tests as needed onstringer-stiffener structure.Cost/Ouration: $280K, 3 y e a r s

m DUCTILE FRACTURE MECHANICS FOR SHIP STEELSObjective: To apply the newly developing fracture mechanics tech-nologies for ductile metals to ship steels.Flethod: Analytical study of new ductile fracture mechanics conceptsand small-scale experimental confirmation.Cost/Duration $60K, 2 years

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/ Hog JOINING cOPPER-NICKEL TO STEEL/ Objective: To provide a production process for joining Cu/Ni sheathsto steel..

Met hod: Experimental development of effective methods of joiningthese dissimilar al loys.Cost/Duration: $1OOK, 1+ years.Prerequisite: Existing support projects.

Mlo EFFECT OF SHEATHING ON SKIN FRICTIONObjective: To increase operating efficiency by reducing fuel consump-tion gained by lowering skin friction of hulls free of fouling.Method: Experimental demonstration of benefits of sheathing to skinfriction on a 200-ft. coastal tanker and experiments to o p t i mi z ec o a t i n g s y s t e m.Cost/Duration: $250K, 3 years.

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Fo 1 FITNESS FOR SERVICE

Fabrication Goal Area

CRITERIAObjective: To minimize weld repair via the establishment of nationalweld acceptance standards based on fitness for service criteria.Method: Establish inspection acceptance standards based on fracturemechanics principles applied to weld defect types and sizes.Cost/Duration: $6oK, 1 year

F02 WELD INSPECTION AND REPAIR STANDARDSObjective: To reduce the incidence of unnecessary weld repairsMet hod: A review of structural performance of post-war ships and NDTexperience.Cost/Duration: $6oK, 1 yearPrerequisite: FO1

F03 ULTRASONIC INSPECTIONObjective: To produce standards and improved procedures for the .ultrasonic inspection of marine structures.Method: An experimental development program to adapt improved ultra-sonic techniques to weld inspection.Cost/Duration: $1,000K, 5 years

F04 NONDESTRUCTIVE ON-LObjective: To provwelding.

Method: Evaluation

NEde

INSPECTION TECHNIQUEmeans of continuous monitoring of production

existing on-line inspection devices, such asacoustic emission, ultrasonic,-holographic methods. ( Work of theElectric Power Research Institute should be consulted.)Cost/Duration: $250K, 2 yearsPrerequisite: F02

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F Ci 5

F06

F07

FOM

CAD/CAM DATA BASE FORMATSObjective: To provide a consensus for a format of CAD/CAt4~generatedstructural information for easy transfer from designer to lead tofollow yards and for data retrieval to monitor production.He t hod: Develop a format specification of CAD-generated structuraldigital information for efficient transfer between designers and yards.Cost/Duration: $220K, 2 years

OUTFIT DESIGN SYSTEM SPECIFiCATIONObjective: To provide user and systems specifications for a CAD systemembodying prevailing or contrived component, arrangement and systemstandards.Method: Use industry consultants to develop user specifications anda systems analyst for the systems specifications.Cost/Duration: $21OK, 1 year

REVIEW OF INDUSTRIAL ENGINEERING APPLICATIONSObjective: An informational review of the logic and principles ofI.E. that can be applied to shipbuilding.Hethod: Generation of a short informational report to the industry .Cost/Duration: $40K, 4 year

SHIPYARD PRODUCTION CONTROLObjective: To define the logic and principles of quantitative produc-tion control techniques including control of materials.Method: Approach is to seek integration with CAD/CAtl and other manage-ment information systems. An industry application manual should result.Cost/Duration: $250K, 2 yearsPrerequisite: F07

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F09 DESIGN DETAILS TO AID PRODUCTIONObjective: To identify simple or cheap alternative designdetails from the perspective of production efficiency.Method: A review of current data and interviews with interested andknowledgeable personnel to develop design improvements.Cost/Duration: $60K, 1 year.

F1O DESIGN-FOR-PRODUCTION MANUALObjective: To provide a comprehensive design guidance manual toillustrate design methods and details leading to simplicity and efficiencyof fabrication with no compromise of structural function.

Method: Gathering of state of the art data from here and abroad, prepara-tion of a draft manual, collection of comments, and publication of amanua 1.Cost/Duration: $75K PIUS $25K per year for revisions.Prerequisite: FO9

F11 WELDING ROBOTS AND ADAPTIVE CONTROLSObjective: To improve welding quality and productivity by in-processsensing devices and adaptive control techniques, including roboticequipment.Method: Laboratory work, computer simulations, and equipment development..Cost/Duration: $500K, 5 years

F12 IMPROVED ~LDING METHODS AND CONSUMABLESObjective: To provide and qualify for shipyard qualificat ion, improvedelectrodes and filler metals for welded fabrication of marine structures,providing enhanced mechanical properties, high deposition rates andlow levels of contaminants.Method: Laboratory development workCost/Duration: $1,000K, 5 years

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Reliability Goal Area

RO1 REL I AB I L I T YOb j e c t i v e :express re

(a):

(b) :

(c) :

(d) :

Co s t / Du r 4 t

A NA L Y SI ST o p r o v i d e a c o n c e p t , model and procedures to assess andability levels.Model, Concept and InputMethod: Ex t e n d a n d modify shoreside existing reliabilitymodels to ship applications.Technology Transfer from Other SourcesMethod: Obtain and apply model information from othersources.Mo d e l V e r i f i c a t i o n T e s t P l a nMet hod: Exercise model to determine sensitivity to inputvariations. Develop set of critical situations to beevaluated by test and by service.Validation by S