Proceedings of the 6th International Conference Behaviour of Offshore Structures, BOSS’92, London, UK, Volume 1 (summary)

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MASSACHUSETTS INSTITUTE OF TECHNOLOGY * USA THE NORWEGIAN INSTITUTE OF TECHNOLOGY * NORWAY D E U T UNIVERSITY OF TECHNOLOGY * THE NETHERIANDS

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I N T E R N A T I O N A L C O M M I T T E E

PROFESSOR C CHRYSSOSTOMIDIS Massachusetts Inslitute of Technology PROFESSOR T MOAN

University of Trondheim PROFESSOR P PRATT

Imperial College of Science Technology and Medicine PROFESSOR J WOLTERS

Technical University of Delft

N A T I O N A L O R G A N I S I N G C O M M I T T E E

PROFESSOR P HOLMES

Imperial College of Science Technology and Medicine PROFESSOR M H PATEL

University College London PROFESSOR P PRATT

Imperial College of Science Technology and Medicine PROFESSOR R EATOCK TAYLOR

University of Oxford

Managed on behalf of the Committee by Robert Gibbins -BOSS 92 Secretariat * BPP Technical Services Limited

TECHNISCHE UNIVERSITEIT

BEHAVIOUR O F OFFSHORE

STRUCTURES

P R O C E E D I N G S O F T H E S I X T H INTERNATIONAL

C O N F E R E N C E

VOLUME ONE

E D I T E D B Y

MINOO H P A T E L

AND

R O B E R T GIBBINS

BPP T E C H N I C A L S E R V I C E S L T D

LONDON

Proceedings ofthe Sixth International Conference on the behaviour of offshore structures, 7 -at Imperial College of Science, Technology and Medicine, London.

10 M y 1992 held

Secretariat

Behaviour of Offshore Structures . Copyright (c) 1992 by B P P Technical Services L t d . All rights reserved. No part of this publicaüon may be

reproduced, stored in a retrieval system or distributed in any form or by any means without the pnor wntten permission of the publisher.

B r i t i s h L i b r a r y catalogue - in - Publication D a t a . A catalogue r e c o r d for this book is available f r o m the B r i t i s h L i b r a r y .

I S B N 1 874612 00 5 Volume 1. (pblc)

I S B N 1 874612 02 1 Set of 2 volumes, (pbk)

Printed by Vail Printers Limited

CONTENTS

Committee and Sponsors Preface

Volume 1

S E S S I O N A l - P L E N A R Y

PROGRESS THROUGH EVOLUTION R.H Bond

S E S S I O N A2 - E V A L U A T I O N O F P R E D I C T I O N S B V N U M E R I C A L H Y D R O D Y N A M I C A N A L Y S I S

A COMPARATIVE STUDY ON COMPUTED MOTION RESPONSE FOR FLOATING PRODUCnON PLATFORMS: DISCUSSION OF PRACTICAL PROCEDURES

KHerfjord and F.G Nielsen

LOW FREQUENCY VERTICAL FORCES ACTING ON A SUBMERGED BODY: A COMPARISON BETWEEN THEORY AND EXPERIMENTS

L Boudel. R Coinle and B Molin

SENSmVITY OF WAVE LOADS TO THE DISCRETIZATION OF BODIES JJ^ Newman and C.-H Lee

S E S S I O N A3 - S T R U C T U R A L R E L I A B I L I T Y A N A L Y S I S

RECENT JAPANESE RESEARCH ACnVITEES ON STRUCTURAL R E L L S l B D J T Y OF SHIPS AND OFFSHORE STRUCTURES

S Machida, H Itagaki, T Oishi and K Ishikawa 5 7 RELLaLBILFTY ANALYSIS SYSTEM FOR OFFSHORE STOUCTURES-RASOS

J.T Gierlinski 5 LARGE ADMISSIBLE PERTUBATIONS APPROACH TO RÉLL\BILrTY: GLOBAL FAILURE EOUATIO^S FOR

ELASTICyPLASTIC MATERLVL BEHAVIOUR

E Beyko, M.M Bernilsas 5

S E S S I O N A4 - F O U N D A T I O N AND I N S T A L L A T I O N E N G I N E E R I N G

INNOVATTVE FOUNDATION SYSTEMS SELECTED FOR THE SNORRE FIELD DEVELOPMENT II.P Christophersen, S Bysveen and OJ Stove

ANALYSIS OF EXACT INSTALLATION OF A GRAVITY BASED STRUCTURE T Vinje, T Marthinsen and J.M Holwech

FOUNDATION BEHAVIOUR O F T H E FRIGG CDPl PLATFORM S Lacasse, L Robber stad, P Boisard and K Ohm

S E S S I O N AS • T H E O C E A N E N V I R O N M E N T

COMBINED EDDY CURRENT/HURRICANE DESIGN CRITERIA FOR DBEPWATER GULF OF MEXICO STRUCTURES

KJ Schaudt. M W Spillam. V J Cardone 109 LARGE-SCALE VORTICES IN THE OCEAN AND UPWELLING

GS Triantafyllou and AA Dimas 121 ONTHE KINEMATICS OF LARGE OCEAN WAVES

P.H Taylor 134 WIND-WAVE DMTERACnONS

CSwan 146 DIRECnONAL DESIGN WAVE COMPUTATION - AN EWESTIG ATION

SSBhatA.B.UNayak.VSamUaimwandM.CDeo 158

S E S S I O N A6 - S T R U C T U R A L R E L I A B I L I T Y A P P L I C A T I O N S

AGHNG OFFSHORE STRUCTURES. A REVIEW OF UK AND US RESEARCH

J.V Sharp. WJ Supple and CE Smith S UNCERTAINTIES ASSOCIATED WITH STRUCTURAL DESIGN OF RING STIFFENED TUBULAR X)INTS

N Tahan. N.W Nichob, J.V Sharp and S.YA Ma S CHARACTERISATION OF THE RESIDUAL STRENGTH OF STRUCTURES WTTH APPUC ATION TO

RELIABILTTY ASSESSMENT J Gierlinski and E Yarimer

ANALYSIS OF TURRET MOORED STORAGE VESSEL FOR THE ALBA FIELD JP Laures and W.C de Boom

WAVE CROSS-CURRENT INTERACHON ON THE DRIFT FORCES OF A MOORED TANKER RM.M Huijsmans

A DISCRETE ELEMENT METHOD ON A CHAIN TURRET TANKER EXPOSED TO SURVIVAL CONDmONS A Dercksen and J.E.W Wickers

THE STATIC AND DYNAMIC ANALYSIS OF MOORED VESSELS IN IRREGULAR SEAS A .K Brook

THE DESIGN WAVE CONDmONS FOR DETERMINING WAVE DRIFF FORCES ON MOORED SHIPS AND SEMI-SUBMERSIBLES

NS Miller and P.M Wilson

171 EFFICIENT R E U A B I U T Y BASED DESIGN OF RING AND STRINGER STIFFENED CYLINDERS UNDER

COMBINED LOADS

P.K Das, D Faulkner and RA Zimmer 180 STRUCTURAL INTEGRITY ASSESSMENT AND U F E EXTENSION OF PLATFORMS IN AUSTRALIA AND

SOUTH EAST ASIA

S French. J Seeto and P.G Dominish ^

S E S S I O N A7 - T U R R E T M O O R E D F L O A T I N G P R O D U C T I O N S Y S T E M S EXTREME MOTIONS AND ANCHOR LINE LOADS INTURRETMOORING SYSTEMS

I Fylling. CT Stansberg and K Mo 1^'

211

225

238

251

S E S S I O N B I - P L E N A R Y F L U I D IJOADING R E S E A R C H - F U T U R E D I R E C T I O N S T Sarpkaya 283 S E S S I O N B2 - L O A D I N G & R E S P O N S E O F C Y L I N D E R S - 1 L O A D I N G A N D R E S P O N S E O F A C I R C U U V R C Y L I N D E R I N O S C I L L A T O R Y F L O W A T C R m C A L R E Y N O L D S N U M B E R S

J.R Chaplin and VUM.R Lakkoju S

M E A S U R E M E N T A N D P R E D I C T I O N O F R E S P O N S E O F C I R C U L A R C Y L I N D E R S I N O S C I L L A T I N G F L O W

P. W Bearman, X.W Lin and P.R Mackwood 29 7

R E S P O N S E O F A C I R C U L A R C Y L I N D E R I N R E G U L A R A N D R A N D O M O S C I L L A T O R Y F L O W A T K C = 10

A Slaouti and P.K Stansby 3{)g

S E S S I O N B3 - C O M P A R I S O N O F D E S I G N P R E D I C T I O N S W I T H F U L L S C A L E F O R F I X E D S T R U C T U R E S

E X T R E M E S T O R M L O A D I N G O N F D C E D O F F S H O R E P L A T F O R M S

P.S Tromans. J.W van de Graaf, M.Efthymiou, L Vanderschuren and P H Taylor 325

D Y N A M I C B E H A V I O U R O F D R I L L I N G D E R R I C K O N S T E E L J A C K E T P L A T F O R M : C O M P A R I S O N B E T W E E N N U M E R I C A L A N D E X P E R I M E N T A L R E S U L T S

V Gusella, O Spadaccini and A Vignoli 337

M E A S U R E D J A C K - U P R E S P O N S E A N D S P U D C A N-S E A F L O O R I N T E R A C T I O N F O R A N E X T R E M E S T O R M E V E N T

W.O McCarron and M.D Broussard ^49

S E S S I O N B4 - C O M P A R I S O N O F D E S I G N P R E D I C T I O N S W I T H F U L L S C A L E A N D M O D E L S C A L E T E S T S

T H E B E N E F I T S A N D D I F H C U L T E S I N M E A S U R I N G O F F S H O R E V E H I C L E B E H A V I O U R

GJ Lyons, A.D Walkins and D.T Brown ^65

E X T R E M E O F F S E T S O F COMPLIANT S T R U C T U R E S : E X P E R I M E N T A L NUMERICAL A N D T H E O R E n C A L R E S U L T S

M Dogliani, F Galeazzi an MJ Sterndorff 37g

P R O B A B I U S T I C A N A L Y S I S A N D I N T E R P R E T A T I O N O F W A V E L O A D I N G A N D R E S P O N S E O F T H E C B T C O M P L L \ N T C Y L I N D E R U N D E R R A N D O M W A V E S

R Burrows, R.G Tickell and D Homes

388

I N T E R P R E T A T I O N OF BUOY M E A S U R E M E N T S I N DIRECnONAL S E A S

S E S S I O N BS - L O A D I N G A N D R E S P O N S E O F C Y L I N D E R S - n

M E A S U R E M E N T S O F T H E H Y D R O D Y N A M I C D A M P I N G O F C I R C U L A R C Y L I N D E R S

PW Bearman and PH Mackwood

O N W A V E FORCE A N A L Y S I S U S I N G S Y S T T E M IDENTinCATION

K Worden. P.K Stansby. G.R Tomlinson and SA Biltings

W A V E L O A D I N G O N A P A I R O F H O R I Z O N T A L C Y L I N D E R S

E Lambert and A Jamo-Druaux

T H E E F F E C T S O F W A V E S A N D M E A N F L O W O N T H E H Y D R O D Y N A M I C F O R C E S O N C I R C U I J \ R C Y L I N D E R S

R.H Arkell. JMJt Graham and C.Y.-Zhou

H Y D R O E L A S T I C R E S P O N S E A N A L Y S E S O F F L E X I B L E O F F S H O R E S T R U C T U R E S

H Kagemoto and T Waseda

S E S S I O N B6 - C O M P A R I S O N O F D E S I G N P R A C T I C E W T T H F U L L S C A L E F O R F I X E D S T R U C T U R E S A N D T L P S

SPECTRAL FATIGUE A N A L Y S I S THEORY V E R S U S PRACnCE NM Fairweather. P.K Gorf. R£ Corr. R.O Snell and DJ Loader

VALIDATION OF " N E W W A V E T H E O R Y A N D RDWF PREDICTIONS A G A I N S T MEASURED G L O B A L

LOADING ON A NORTH SEA JACKET 7" Elzinga and PS Tromans

APPLICATION OF TENSION LEG PLATFORM PERFORMANCE DATA E.R Jefferys. JA Mercier. S.C Bultema and PJi Erb

MEASURED A N D PREDICTED DYNAMIC BEHAVIOUR OF TOE GULLFAKS C G R A V T T Y PLATFORM ƒ Langen, E Skomedal and O Skjastad

STRUCTURAL RESPONSE A N D FATIGUE A N A L Y S I S OF A MONITORED PLATFORM O Spadaccini and S Biagini

S E S S I O N B7 - F O U N D A T I O N A N A L Y S I S T E C H N I Q U E

FOUNDATION WAVE LOAD TRANSFER FOR PLATFORMS ON RIB FOUNDATIONS HJLuger and P Meijers

OFFSHORE SKIRT PENETRATIW IN CLAY IN TOE GEOCENTRIFUGE A.GJ Hjortnaes-Pedersen and A Berauijen

A N IMPROVED CALCULATION METHOD FOR CONDUCTOR SETnNG DEPTHS I N SAND GJM Schotman and B Hospers

T H E BEHAVIOUR O F DISPLACEMENT P I L E S IN G L A C L \ L T I L L

S E S S I O N C l - P L E N A R Y

OFRSHORE STRUCTURAL R E U A B I U T Y ASSESSMENT - FROM RESEARCH TO REAUTY7

G Edwards and JJi Vugts S

S E S S I O N C2 - T E N S I O N L E G P L A T F O R M D Y N A M I C S

NON-UNEAR HYDRODYNAMIC ANALYSIS O F T L P S IN EXTREME WAVES: SLENDER BODY AND DIFFRACnON THEORIES COMPARED

R Eaiock Taylor, R.C.T Rainey and DM Dai 5 69 EXPERIMENTAL MEASUREMENT OF SBCONIW)RDER SUM-FREQUENCY OSCILLATIONS OF ATENSION-L E G PATENSION-LATFORM

T Matsui. Y Sakoh and T Nozu 584 COMPARATIVE EVALUATION OFTENSIONED L E G PIATFORMS WTTH REDUCED TETHER TENSION

MMPaielandHIfark 599

S E S S I O N C3 - S T R U C T U R A L I N S P E C T I O N

INSERVICE INSPECTION PLANNING FOR STEEL OFFSHORE STRUCTURES USEMG R E U A B I U T Y METHODS

I Lotsberg and M J Mar ley 517 R E U A B I U T Y BASED INSPECnON PLANNING

H Carstens, C Eilersen and H O Madsen S A B A Y E S L W INSPECnON PROCEDURE APPUED TO OFFSHORE STEEL PLATFORMS

J J Jensen and PT Pedersen 529 ACFM INSPECTION OF OFFSHORE STRUCTURES

W.D Dover, JJi Rudlin. C Monahan and M Lugg 643

S E S S I O N C4 - C O M P A R I S O N O F D E S I G N P R E D I C T I O N S W I T H F U L L S C A L E F O R F O U N D A T I O N S CORRELATION O F T H E RESULTS FROM FIELD EXPERIMENTS WTTH D^STRUMENTED MODEL PILES DM LONDON C L A Y AND LABORATORY RING SHEAR INTERFACETESTS

T.E Tika-Vassilikos. AJ Bond and RJ Jardine 1 INSTRUMENTATION O F T H E SKIRT PILED GULLFAKS C GRAVTH' PLATTORM FOR PERKDRMANCE

MONTTORING

F Myrvoll ^.^^ INSTRUMENTATION FOR MONITORING THE INSTALLATION AND PERFORMANCE OF THE CONCRETE

FOUNDATIWJTEMPLATES FOR THE SNORRETENSION LEG PLATFORM R Jonsrud and G Finnesand

690 OBSERVATIONS ON DRAINAGE CONTROL EFFECTS ON GULUAKS CGRAVTTY STRUCTURE

Volume 2

THE DESIGN OFTHE INSTALLATION AND OFFSHORE COMPLEHON OF THE EKOFISK PROTECnVE BARRIER

HAJde Ridder

733

744 SESSION C9 • M A T E R I A L S T E C H N O L O G Y

HIGH PERFORMANCE COMPOSITE TUBES FOR DEEPWATER RISERS

C Sparks, P Odru, M Auberon amd G Metivaud ' 2 3 BUCKLING BEHAVIOUR OF COMPOSITE GFRP CYLINDRICAL PANELS UNDER A X I A L COMPRESSION

M K Chryssaruhopoulos, K D Kim and P J Dowling

UNDERSTANDING BRITTLE SHEAR FAILURE I N CONCRETE OFFSHORE STRUCTURES J Blaauwendraad and Z Ping Wu

SESSION CS - V O R T E X INDUCED V I B R A T I O N S

HYDRODYNAMICS OF LARGE AMPLTTUDE CABLE VIBRATIONS IN CURRENTS

W.W Massie, JA Battjes, M.W Dijkman and VM Thumann '59 THE SIGNIHCANCE OF WATER DEPTH OF VORTEX INDUCED VIBRATIONS OF MARINE RISERS

J Fang and GJ Lyons

THE INTRODUCTION OF A SECOND PHASE AS A MEAN OF REDUCING VORTEX EDUCED VIBRATIONS A Moros and C Swan

THE USE OF HELICAL STRAKES TO SUPPRESS VORTEX INDUCED VIBRATION GS Jones and WS Lamb

SHIELDING AND BLOCKAGE MODEL FOR OFFSHORE PLATFORMS K.F Lambrakos and H Beckmann

SESSION C6 - S T R U C T U R A L A N A L Y S I S AND F A T I G U E OF F I X E D P L A T F O R M S

DESIGN IMPUCATIONS FOR NEW DRAFT FATIGUE GUIDANCE FOR TUBULAR JOINTS: CASE STUDIES R Nataraja, D Loader, J.V Sharp and N.W Nichols

A METHODOLOGY FOR THE ASSESSMENT OF FATIGUE CRACKS IN OFFSHORE JACKET STRUCTURES / Haswell and R Murray

LOAD FACTOR CALIBRATION FOR THE GULF OF GUINEA ADAPTATION OF API RP2A-LRFD M Birades, C A Cornell and B Ledoigt

776 791 804 836 S 851 866 LIMIT STATE CODE CHECKING OF OFFSHORE CONCRETE STRUCTURES

MJ Bailey. N.F.O Evbuomwan, NDJ' Barlirop and T.Hodgson

SESSION C7 - S H E L L T R O L L P L A T F O R M F O U N D A T I O N A N A L Y S I S

SOIL PARAMETERS FOR FOUNDATION DESIGN, TROLL PLATFORM T By and E Skomedal

FOUNDATION DESIGN, TROLL PLATFORM

B Hansen, F Nowacki, E Skomedal and J Hermstad 921 CLAYBEHAVIOUR UNDER IRREGULAR C Y C U C LOADING

K.H Andersen, R Dyvik, Y Kikuchi and E Skomedal 937 EFFECTIVE STRESS CONCEPT FOR DYNAMIC STIFFNESS OF C L A Y

G Svano, H Lango. C Madshus and E Skomedal 95 j EXTREME DYNAMIC RESPONSEOFTHETROLLGRAVTTYPLATFORM

D Karunakaran. BJLeira, O Skjastad and E Skomedal 959 S E S S I O N C8 - J A C K - UP D E S I G N A N A L Y S I S

JACK-UP

ELEVATED

JACK-UP

PLiu, W.W Massie, J.G Wolters and J Blaauwendraad jqO]

P I S T T O R J S " ^ ' ^ ^ ^ ' ^ ^ ^ ^ ^ ^ ^ ^ ^^^^

D Karunakaran, BJLeira, N.Spidsoe. O.TGudmestad and T Moan 1015

S E S S I O N D I - P L E N A R Y

mSTORICALOVERVlEW OF GEOTECHNICAL DESIGN IN THE NORTH SEA

Tor Inge Tjelta ^^^^ GEOTECHNICAL DESIGN AND ENGINEERING FOR THE 90'S

F.E. Toolan

S S E S S I O N D2 - L O W F R E Q U E N C Y DAMPING

WAVE DRIFT DAMPING OF A TURRET MOORED SHIP

V Aanesland, K.E Kaasen and J.R Krokstad j ^^ j L g m i E Q U E N C Y DAMPING P R E D I C ^ ^ ^

G£ Hearn and P Goodwin

1066

OSïi?lL°S!ïSSS^''''^°'''''^'^'^™^^

A Nestegird and T Vada

S E S S I O N D3 - D Y N A M I C R E S P O N S E O F F L O A T I N G S T R U C T U R E S

EXPERIMENTAL AND THEOREnCAL INVESTIGATION INTO THE ROLL DAMPING OF A SYSTEMATIC SERIES OFTWO DIMENSIONAL BARGE SECTIONS

R.G Standing . G.E Jackson andAK Brook

D4FLUENCE OF LOAD MOTION CONTROL ON THE OPERATIONAL UMITATIONS OF l A R G E CRANE VESSELS IN SEVERE ENVIRCM>nvIENT

G.F Clauss and T Riekert

DYNAMIC RESPONSE OF A MULTI HINGE ARTICULATED TOWER COUPLEDTO A SHIP T.K Thomas and C Ganapalhy

S E S S I O N D4 - S A F E T Y I S S U E S

1112

1126

STRUCTURAL CONSEQUENCE ANALYSIS FOR QRA G Home and D Harrison

MANAGING RISK ASSESSMENT FOR T H E TIFFANY PLATFORM STRUCTURE J Kennedy, P Linzi, P Dennis

BLAST RESISTANT RETROFTT OF AN OFFSHORE MODULE: AN OVERVIEW

JA Alexander and JA Jones 1143

S E S S I O N DS - W A V E D R I F T B E H A V I O U R

W A V E D R I F T F O R C E S I N S H A L L O W W A T E R j ^ ^ ^

JA Pinkster and RJiM Huijsmans

SLOWLY VARYING DRIFT FORCES I N DIRECnONAL WAVES ^^^^ YInoueandW.YXue

L O N G D U R A T I O N M O D E L T E S T S F O R L O W F R E Q U E N C Y B E H A V I O U R O F F L O A T I N G O F F S H O R E

S T R O C T U R E S I N L O N G A N D S H O R T C R E S T E D W A V E S ^ ^ ^ ^

MJ Sterndorff and J Skourup

M O D E L S C A L E E X P E R I M E N T S O N E X T R E M E S L O W D R I F T M O T I O N S DM I R R E G U L A R W A V E S

CT Stansberg

T H E S L O W D R I F T R E S P O N S E O F M U L T I L E G S T R U C T U R E S I N I R R E G U L A R A N D R A N D O M W A V E S

PD Sclavounos arui OJ Emmerhoff

M E A N Y A W M O M E N T O N F L O A T I N G B O D I E S A D V A N C I N G W T T H A F O R W A R D S P E E D DM W A V E S

J Grue and E Palm

1207

1223

1238

S E S S I O N D6 - H Y D R O D Y N A M I C S AND S T R U C T U R A L M E C H A N I C S O F F L E X I B L E P I P E S

DESIGN METHODS FOR FLEXIBLE RISERS J253 CJA Larsen, BJ Leira, A Olufsen and N Sfidahl

LOOP FORMATION OF MARINE CABLES AND UMBIUCALS DURDJG m S T ALLATTON ^^^^ Z Tan and J A Witz

DAMPDMG AND HYSTERESIS EFFECTS ON THE BEHAVIOUR OF FLEXIBLE RISERS ^ G de Boer and HJ van den Boom

A STUDY OF THE BEHAVIOUR OF A LONG AND FLEXIBLE PIPE Dl THE WATER ^ M Ohkusu

S E S S I O N D7 - L I Q U I F I C A T I O N AND S C O U R

PULL-OUT CAPACITY ANALYSES OF SUCnON ANCHORS FOR TENSION LEG PLATFORMS KM Andersen, R Dyvik and K Schroder

B A Y E S L W UPDATING OF SETTLEMENT PREDICTION AH Tan and FNadim

UQUfflCATION OFTRENCH FILL AROUND A PIPELINE IN THE SEABED M.B de Groot and P Meijers

LOCAL SCOUR NEAR SUBMARINE PIPELINES ON A COHESIVE BCmDM ETJM Pluim - van der Velden, E W Bijker

EFFECT OF C Y C U C PRESTRAINING ON THE UQUIHCATION OF SAND S Teachavorasinskun, F Tatsuoka, K Kenkyo and K Yasuhara