Lab. V . Scheepsbouwkunde
Technische Hogeschool
Delft
2 8 JUN! 1988
ARCHIEF
Pigsa -2-1
BOSS 88
Proceedings of tlie International Conference
on Behaviour of Offshore Structures
IVondheim, Norway June 1988
Edited by
T. Moan, N. Janbu and O. Faltinsen
V O L U M E 1
TAPIR P U B L I S H E R S
TVondheim, Norway
© TAPIR PUBLISHERS 1988 ISBN 82-519-0855-8
This publication may not be reproduced, stored in a retrieval system or transmitted in any form or by any means; electronic, electrostatic, magnetic tape, mechanical, photo-copying, recording or otherwise, without permission.
Cover design by LeifGaustad
based on a painting by Jostein Kirkerud. Printed by Tapir
In order to make this volume avaUable as economically and rapidly as possible, the a typescripts have been reproduced. Unfortunately, this method has its typographical tions, but it is hoped that they in no way wiU distract the reader.
ORGANIZATION
International Organizing Committee 1988
Professor C. Chryssostomidis (Massachusetts Institute of Technology (MIT), USA Professor R. Eatock Taylor University of London, UK
Professor T. Moan (Chairman) The Nonwegian Institute of Technology, Norway (NTH)
Professor J. Welters Delft University of Technology, The Nethedands (Delft)
Sclemiflc Committees Geotechnlcs
Professor J. Burland Professor N. Janbu Mr. E.H. de Leeuw
Professor R. Whitman
Hydrodynamics
Professor J.A. Battjes Professor O. Faltinsen Professor J.M.R. Graham Professor J.N. Newman Structures Professor J.J. Connor Professor P.J. Dowling Professor T. Moan Professor J. Wolters
National Organizing Committee
Impenal College, UK NTH, Norway
Deputy managing director,
Delft Geotechnics, The Netherlands MIT, USA
Delft, The Nethedands NTH, Norway Imperial College, UK MIT, USA MIT. USA Imperial College, UK NTH. Norway
Delft, The Nethedands
Professor O. Faltinsen Dr. J. Huslid Dr. K. Hoeg Professor N. Janbu Professor T. Moan Dr. E.M.Q. Roren NTH
Technical Director. Statoil
Director. Norwegian Geotechnlcal Institute NTH
NTH
Director, Det norske Veritas
Sponsors
Aker Engineering Det norske Veritas A/S Norske Shell Nonwegian Contractors
Norwegian Geotechnlcal Institute Statoil
The Foundation for Scientific and Industrial Research at NTH (SINTEF) The Nonwegian Society of Chartered Engineers
P R E F A C E
The 1988 conference on Behaviour of Offshore Structures follows previous conferences held in Trondheim (1976), London (1979), Cambridge, Massachusetts (1982) and Delft (1985).
Major technical developments have been accomplished in the field of offshore structures, but considerable scientific and practical advances are srill to be made. The exploitation of subsea hydrocarbons in increasing water depths and more severe environments, together with low oil prices, present significant challenges to marine technologists in pursuit of new, cost-effective systems. BOSS conferences are intended to provide an international forum where those involved in the design and operation of offshore structures can meet and exchange ideas and information about how to tackle these challenges.
The conferences are organized in sessions on three major subjects: - Geotechnics
- Hydrodynamics
- Structural mechanics and design
The Organizing Committee had a difficult task in selecting the 97 papers to be presented. 275 abstracts were submitted, of which many were of outstanding quality, but lack of time and space made it impossible to include them all. hi addition to the submitted contributions, four speakers have been invited to address the conference in plenary sessions. The
organizers would like to thank the authors, especially the plenary lecturers,
for theh- cooperation and efforts, without which the conference would not have been possible. We hope that the conference will contribute to the further development of offshore technology.
The conference is arranged by the Norwegian InstiUite of Technology in cooperation with London University, Massachusetts histitute of Technology and Delft University of Technology. We would like to thank our colleagues in the cooperating institutions for their active participation, and look forward to the continued success of BOSS conferences in die future.
T o r g ^ Moan Chairman
TABLE OF CONTENTS
VOLUME 1
K E Y L E C T U R E S
Knut Am
Ekofisk Subsidence: The Problem, the Solution, and the Future 19
Wagner Freire
Recent Aspects o f Deep Water Offshore Production in Brazil 41
Pdl Bergan
Use o f Supercomputers in Analysis o f Offshore Structures 61
GEOTECHNICS
R. J . Jardine, D. M. P. Potts, W, Mcintosh
Predictions and Measurements of the Load Displacement Behaviour
of the Hutton T L P Foundations 79
A. J . Whittle, M. M. Baligh, A . S. Azzouz, A. M. Maiek
A Model for Predicting the Performance o f T L P Piles in Clays 97
D. M. Potts, M. E . Jones, O, P. Berget
Subsidence Above the Ekofisk Oil Reservoirs 113
N. Barton, A . Makurat, L . Hérvik, G . Vik, S. Bandis, M. Christiansen, A. Addis
The Discontinuum Approach to Compaction and Subsidence Modelling
as Applied to Ekofisk j29
S. O. Christensen, N. Janbu, M. E . Jones
Subsidence Due to Oil-Gas Production I43
E . DiBiagio, T. Dyken
A Comparison o f Measured and Calculated Strains and Long-Term
Creep in Concrete Gravity Base Structures I59
T. I. Tjelta, A.A. Skotheim, G . Svane
Foundation Design for Deepwater Gravity Base Structure
With Long Skirts on Soft Soils I73
L . Grande, N. Janbu, H . Lange
D. W. Hight, D. M. Potts, T. I. Tjelta
Finite Element Analyses o f a Deep Skirted Gravity Base 20y
S. Nordal, B. Bostrem, F. J . Fredriksen
A n Effective Stress Soil Model Applied to an Undrained Finite Element Analysis o f a Gravity Platform
B. Andreasson, H . P. Christopherscn, T. J . Kvalstad
Field Model Tests and Analyses of Suction Installed Long-Skirted Foundations. 243
K. Arnesen, R. Dahlberg, H . Kjeey, C A. Karlsen
Soil-Structure-Interaction Aspects for Jack-Up Platforms 2 i y
E. Kodaissi, P. Narzul
Modelling of Pipe/Soil Interactions in Flexible Risers 2/y
T. Sotberg, K. E Lambrakos, S. Remseth, R. L . R Verley, W. R. Wolfram Jr.
Stability Design of Marine Pipelines 295
K. H . Andersen, R. Lauritzsen, R. Dyvik, P. M. Aas
Cyclic Bearing Capacity Analysis for Gravity Platforms; Calculation Procedure,
Verification by Model Tests, and Application for the Gullfaks C Platform 311
N. Janbu, R. Roque, H . Langa, T. L Tjelta
Cyclic Load Testing of Contractant Clays f r o m Gullfaks C
Cvan Zandwijk, R. S. Beurze , ^
The Impact of Pile Inclination on the Design of Platform Foundations 343
H . Lange, N. Janbu, G. P. Bemardes, T. L Tjelta
Drivability of Large Pipe Piles Analysed by Case Records -ioi
M.A. Allman, C Y . Lee, H.G. Poulos
Behaviour of Model Grouted Piles in Cemented and Uncemented Calcareous Soils
J . M. Hamilton, J . D. Murff
Probabilistic Assessment o f the Foundation Collapse Strength ot Piled Offshore Platforms
379
393
N. S. Rad, S. SoIUe, T Lunne, B. A . Torstensson
A New Offshore Soil Investigation Tool for Measunng the I n Situ Coefficient of Permeability and SampUng Pore Water and Gas
419
E A . van Beek, R. Bijker, H . G . Wind
Simulation of Erosion and Sedimentation Around Marine Structures by Means of a Numerical Model
A . M . M a l e k , A . S . A z z o u z , M , M . B a U g h , A . J . W h i t Ü e
Behavior of Pile Foundations Supporting Tension Leg Plattorms
VOLUME 2
HYDRODYNAMICS
Y. Lecointe, J . Piquet
Computation of the Characteristics o f the Wal<e Past an Oscillating Cylinder . . 457
R W. Bearman
Wave Loading Experiments on Circular Cylinders at Large Scale 47|
P. Sulmont, D. R. Rajaona
Measurements of the Drag Forces on an Inclined Circular Cylinder
in a Uniformly Accelerated or Decelerated Motion 489
J . R. Chaplin
Non-linear Forces on Horizontal Cylinders in the Inertia Regime
in Waves at High Reynolds Numbers 505
Y. K. Vyas, A . Lohrmann, J . C Heideman, F. E . Dahl, J . A. Vermersch
Storm Driven Current Profiles for Design o f Offshore Platforms 519
D. J . Maull, D. Kaye
Oscillations o f a Flexible Cylinder in Waves . 5 3 5
M. S. IHantafyllou, K. Engebretsen, J . S. Burgess, D. R. Youreer, M. A. Grosenbaugh
A Full-Scale Experiment and Theoretical Study o f the Dynamics
of Underwater Vehicles Employing Very Long Tethers 549
B. M. Sumer, J . R-edsei^ H . Gravesen
Vibrations o f Pipelines in Scour Trenches 565
J . M. R. Graham
Calculation o f Hydrodynamic Damping o f Offshore Structures 579
E . Le Marchand, C Berhault, B. Molin
Low Frequency Heave Damping o f Semi-Submersible Platforms:
Some Experimental Results 59j
J . N. Newman, P. D. Sclavounos
The Computation o f Wave Loads on Large Offshore Structures 605
R. Zhao, O, Faltinsen, J . R. Krokstad, V. Aanesland
Wave Current Interaction Effects on Large Volume Structures 623
C R Pesce, J . A . R Aranha
R. Eatock Taylor, S. M. Hung, K. L . Mitchell
Advances in the Prediction o f Low Frequency D r i f t Behaviour 0 5 i
C T, Stansberg, J . R. Krokstad, O. H . Slaattelid
Model Tests on Non-Linear Slow-Dri f t Oscillations Compared
to Numerical and Analytical Data ° ° '
M. H . Kim, D. K. P. Yue
The Nonlinear Sum-Frequency Wave Excitation and Response of a Tension-Leg Platform
R. Cointe, B. Molin, R Nays , , nn^
Nonlinear and Second-Order Transient Waves in a Rectangular Tank /u:>
S.Takezawa,K.Kobayashi . . . . ^ » ^
On the Motion Characteristics of Semi-Submersibles in Short-Crested Irregular Waves
R. R Dallinga, R. H . M. Huijsmans, J . A. Pinkster
Combined Statistics o f First and Second Order Motions of Semi-Submersibles
A. E . Mynett, J . Bosma, J . A. Keuning, J . Gerritsma
Laboratory Simulation o f Ship Motions in Directional Seas '53
E R Jeff cry s
Directional Wave Spectra Inferred f r o m T L P Motion and Wave Elevation 773
O. T. Gudmestad, J . M. Johnsen, J . Skjelbreia, A . Terum
Regular Water Wave Kinematics 789
P.Justesen , j
Hydrodynamic Forces on Large Cylinders m High Reynolds Number Oscillatory Flow
A. Bliek, G . Klopman w » i
on-Linear Frequency Modelling o f Wave Forces on Large Vertical and Horizontal Cylinders in Random Waves
H.T.Hansen,N.G.Skomedal,T.Vada . ^T
A Method for Computation o f Integrated Vortex Induced Fluid Loading
and Response Interaction of Marine Risers in Waves and Current «^i
K. Herfjord, E G . Nielsen „ o
Low Frequency Motion of a Deep Draft Column Stabilized Platform
L . Bergdahl, M. Johansson
Time Simulations of the Motion of a Tension Leg Platform ^ ' ^
R E . Duncan, K. R. Drake, D. Windle , , ,
Jacket to Template Docking Forces: Predicting Full Scale Loads From Results of Physical and Computational Models
VOLUME 3
STRUCTUras
K. Kokkinowrachos, G. Sens
Buckling o f Stringer-Stiffened Cylindrical Shells under Combined L o a d s . . . 915
J . Odland
Improvements in Design Methodology for Stiffened and Unstiffened
Cylindrical Structures g^s E. Corona, S. Kyriakldes
Collapse o f Pipelines Under Combined Bending and External Pressure 953
P. Terndrup Pedersen, J . Michelsen
Large Deflection Upheaval Buckling o f Marine Pipelines 955
T. Moan, W. C Webster
Consequence Analysis of Tether Failure 981
M. Langseth, P. K. Larsen
Dropped Objects. Plugging Capacity o f Steel Plates lOOi
H . C Peters, H . Boonstra
Fatigue Loading on a Single Pile Platform Due to Combined Action of Waves and Currents
1015
D. Ritchie
A Fatigue Crack Growth Model for Thickness Transition Girth Welds 1053
H . H . Snijder, D. R. V. van Delft, O. D. Dijkstra, C Noordhoek
Fatigue Crack Growth ModeUing for Multiple Initiated Cracks at Weld Toes in TUbular Joints
1065 G. M . Brown, R. Holmes, J .
Ken-Fatigue Life Enhancement o f Welded Tubular Joints by Injection or G r o u t . . . . 1081
L . Dossl
A New Perspective in Structural Diagnostics: The Echomechanical Method . . . 1097
B. Jakobsen, R.Agnes
Structural Response o f The Gullfaks C Platform During
Out O f Dock Operation . . . 1II3
J . J . Jensen, E . Thorenfeldt, A. Tomaszewicz
R. Eie, S. Fjeld, C Nygaard, K. A. Nyhus
Floating Concrete Structures The New Deal in Floating Production
G . E Davenport, M. B. Leung, E . Hasle, J . G . Kuang
Concrete Compliant Towers for Deepwater Apphcations i i o i
C A. C v a n der Valk
Factors Controlling the Static Strength of Tubular T-Joints i • ' '
P. J . Dowling, A . S. EInashai, W. Aritenang, B. C Carroll
Failure Mechanisms of Composite Tbbular Connections with Shear Keys
G . Stewart, M. Efthymiou, J . H . Vugts
Ultimate Strength and Integrity Assessment of Fixed Offshore Platforms 12Ü5
D. L Karsan, A. Kumar, S. Y. Hanna
Failure Path Identification for Fixed Offshore Structures Subjected ^^^^ to Fatigue
P Bjerager, R. Leseth, S. R. Winterstein, C A . Cornell
Reliability Method for Marine Structures Under Multiple Environmental Load Processes
C A. Holm, R Bjerager, R. Olesen, H . O. Madsen
System Reliability of Offshore Jacket Structures by Elastic and Plastic Analysis
D. Schaap, R. J . van Foeken, R E . de Winter
Deformation Capacity o f Steel Tubulars Subject to Internal or ^^^^ External Pressure
R Makelainen, R. S. Puthli ^ T ^ T ^ I , , T • »c O 7 R
Semi-analytical Models for the Static Behaviour o f T and DF Tubular Joints . . 1278
R Soroushian, M. S. Alawa ,
Steel Offshore Platforms: Refined Modeling and Optimum Design o f Bracing Elements for Seismic Loads
S. Y. A . Ma, L E . Tebbett „ „
Ultimate Strength of Tubular Welded Joints with Large Beta Ratio
T.Y.Chen,W.S.Shen, Z . Q . L i n . . „• , n ^ i
A Model of Analysis of Buckling Propagation in Marine Pipelines i J J i
W. de Graaf, E C Lange, J . G . Wolters, W. W. Massle
Clump Weights in Flexible Riser Design
A. Engseth, A . Bech, C M. Larsen
Efficient Method for Analysis o f Flexible Risers
p. J. O'Brien, J . F. McNamara
Analysis of Flexible Riser Systems Subject to
Three-Dimensional Seastate Loading I373
R. C Batista, N. Roitam
Damping Effects on Jack-Up Dynamic Response and Design 1389
R. Nerzic, G . Lebas
Uncertainties in Wave Loading f r o m Full-Scale Measurements 1399
F. van Walree, E. Willemsen
Wind Loads on Offshore Structures 1413
B. Jakobsen, D, N. Jenssen
Recent Development of Offshore Concrete Structures 1429
B. Berge
Optimal Deep Water North Sea Jacket Structures I445
G . Solland, E. Frank
Rational Design o f Stressed Skin Offshore Modules 1457
J . L . Black
Comparison of Measured and Calculated Launch Stresses 1473
T. F. Liu, Z. G . Zhou, J . G . Shi
Optimum Design Environmental Criteria for Platform 1483
L . R. Muir, M. A . Maes, R. G. Sexsmith
Calibration and Verification o f the New CSA Code for Offshore Structures . . . 1497
P. E. Skrikerud, E. M. Hall, H . G . Vormedal, E. Ravndal
Investigation o f Damage to an Articulated Crude Loading Tower
Caused by a Tanker Collision I509
