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Intermediate Offshore Foundations [Kõva köide]

  • Formaat: Hardback, 316 pages, kõrgus x laius: 234x156 mm, kaal: 757 g, 34 Tables, black and white; 16 Line drawings, color; 139 Line drawings, black and white; 18 Halftones, color; 2 Halftones, black and white; 34 Illustrations, color; 141 Illustrations, black and white
  • Ilmumisaeg: 21-Jun-2021
  • Kirjastus: CRC Press
  • ISBN-10: 1138353531
  • ISBN-13: 9781138353534
Teised raamatud teemal:
  • Formaat: Hardback, 316 pages, kõrgus x laius: 234x156 mm, kaal: 757 g, 34 Tables, black and white; 16 Line drawings, color; 139 Line drawings, black and white; 18 Halftones, color; 2 Halftones, black and white; 34 Illustrations, color; 141 Illustrations, black and white
  • Ilmumisaeg: 21-Jun-2021
  • Kirjastus: CRC Press
  • ISBN-10: 1138353531
  • ISBN-13: 9781138353534
Teised raamatud teemal:
"Intermediate foundations are used as anchors for floating platforms and ancillary structures, foundations for steel jackets, and to support seafloor equipment and offshore wind turbines. When installed by suction, they are an economical alternative to piling, and also may be completely removed"--

Intermediate foundations are used as anchors for floating platforms and ancillary structures, foundations for steel jackets, and to support seafloor equipment and offshore wind turbines. When installed by suction, they are an economical alternative to piling, and also may be completely removed. They are usually circular in plan and are essentially rigid when laterally loaded. Length to diameter embedment ratios, L/D, generally vary between 0.5 and 10, spanning the gap between shallow and deep foundations, although these are indicative boundaries and the response, rather than the embedment ratio, defines an intermediate foundation.

The first chapters introduce foundation types; compare shallow, intermediate and deep foundation models and design; define unique design issues that make intermediate foundations distinct from shallow and deep foundations, as well as list their hazards that mainly occur during installation. Later chapters cover installation, in-place resistance and in-place response, and miscellaneous design considerations.

There is no general agreement as to which design methods/models are appropriate, so models should only be as accurate as the data. Therefore, several reasonably accurate models are provided together with comprehensive discussion and advice. Example calculations and over 200 references are also included.

This is the first book dedicated to the geotechnical design of intermediate foundations, and it will appeal to professional engineers specialising in the offshore industry.

Preface xiii
Notes from the co-authors xv
1 Introduction 1(6)
1.1 Intermediate foundations
1(3)
1.2 Matching models and data quality for good design
4(2)
1.3 Structure of the book
6(1)
2 Offshore foundation types and mode of operation 7(18)
2.1 Definitions - shallow, intermediate and deep foundations
7(2)
2.2 Modes - shallow, intermediate and deep foundations
9(11)
2.3 Intermediate foundation geometry
20(3)
2.3.1 General
20(1)
2.3.2 Internal stiffeners
20(1)
2.3.3 External stiffeners
21(1)
2.3.4 Protuberances
21(1)
2.3.5 Embedment ratio
21(2)
2.4 Summary of intermediate foundation terms
23(2)
3 Loads 25(6)
3.1 Introduction
25(1)
3.2 Units, sign conventions and reference point
25(3)
3.2.1 Example - units
25(3)
3.3 Structural to geotechnical load conversion
28(2)
3.3.1 Example - load conversion
29(1)
3.4 Geotechnical stresses and strains
30(1)
3.5 Commentary
30(1)
4 Marine geology 31(4)
4.1 Geology, sediment types and depositional environments
31(1)
4.2 Lateral variability top layers
31(2)
4.3 Seafloor conditions
33(2)
5 Loading conditions and soil drainage 35(6)
5.1 Introduction
35(1)
5.2 Drained-undrained
36(4)
5.2.1 Non-dimensional velocity - penetration rate
36(1)
5.2.2 Dynamic drainage factor - dynamic loading of solid piles
37(1)
5.2.3 Laterally loaded pile
38(1)
5.2.4 Generic
39(1)
5.3 Closure
40(1)
6 Hazards, uncertainties and risk minimisation 41(14)
6.1 Introduction and case histories
41(8)
6.1.1 Low penetration resistance during installation in NC clay
41(3)
6.1.2 Excessive misalignment during installation in NC clay
44(2)
6.1.3 Cylinder buckling during installation
46(1)
6.1.4 Sand plug liquefaction during installation
46(2)
6.1.5 Underpressures close to/above critical during installation in competent sands
48(1)
6.1.6 Excessive scour during operation
48(1)
6.1.7 Anchor chain trenching during operation
48(1)
6.2 Hazards
49(2)
6.3 Uncertainties
51(1)
6.3.1 Geotechnical data
51(1)
6.3.2 Geotechnical design
52(1)
6.4 Risk minimisation
52(1)
6.4.1 Ground investigation
52(1)
6.4.2 Geotechnical data
53(1)
6.4.3 Laboratory testing
53(1)
6.4.4 Geotechnical design
53(1)
6.5 Closure
53(2)
7 Investigation programs 55(4)
7.1 Introduction
55(1)
7.2 Desk study
55(1)
7.3 Geophysical and geotechnical
56(2)
7.4 Laboratory
58(1)
8 Design basis 59(20)
8.1 General principles
59(9)
8.1.1 Introduction
59(2)
8.1.2 Installation/retrieval/removal
61(2)
8.1.3 In-place resistance
63(1)
8.1.4 In-place resistance - non-co-planar MH loads
64(4)
8.1.5 In-place response
68(1)
8.2 Sign conventions, nomenclature and reference point
68(1)
8.3 Foundation stiffness and fixity
69(3)
8.3.1 Seafloor VHMT loads
71(1)
8.3.2 Foundation lateral and rotational fixity
71(1)
8.4 Load and material factors
72(1)
8.5 Commentary
73(1)
8.6 Closure
73(6)
9 Installation, retrieval and removal 79(96)
9.1 Introduction
79(1)
9.2 General considerations - suction assistance
79(2)
9.3 General considerations for monopile installation - impact driving, vibratory and drilled and grouted
81(4)
9.4 Best and high estimates - installation resistance
85(1)
9.5 Under-penetration and over-penetration
85(3)
9.5.1 General
85(2)
9.5.2 Under-penetration
87(1)
9.5.3 Over-penetration
87(1)
9.6 Difficult soil profiles
88(2)
9.7 Maximum pump underpressure
90(1)
9.8 Penetration resistance assessment
90(15)
9.8.1 Introduction
90(1)
9.8.2 CPT qc Method
91(1)
9.8.3 CPT method coefficients kp and kf
92(3)
9.8.4 CPT method coefficient αU
95(8)
9.8.4.1 Commentary - steady state
101(2)
9.8.5 Classical bearing capacity method
103(2)
9.9 Landing on sea floor, minimum self-weight penetration and free-fall penetration
105(6)
9.9.1 Landing on sea floor
105(1)
9.9.2 Minimum self-weight penetration
106(1)
9.9.3 Free-fall penetration
107(4)
9.9.3.1 Example - pile free-fall
108(2)
9.9.3.2 Example - pile free-fall case A (suction foundation)
110(1)
9.9.3.3 Example - pile free-fall case B (OWT monopile)
110(1)
9.9.3.4 Example - self-weight penetration cases A and B
110(1)
9.9.3.5 Example - commentary
111(1)
9.10 Installation in clay
111(20)
9.10.1 Base failure in clay
111(2)
9.10.2 Plug heave in clay
113(1)
9.10.3 Clay installation/retrieval example
114(6)
9.10.3.1 Example - clay installation and retrieval
117(1)
9.10.3.2 Commentary
118(2)
9.10.4 Friction set-up in clay
120(1)
9.10.5 Boulders in clay
121(10)
9.10.5.1 Forces on boulder and pile tip
122(4)
9.10.5.2 Refusal
126(1)
9.10.5.3 Refusal example 1 - weak clay with dropstone
126(1)
9.10.5.4 Refusal example 2 - competent clay/glacial till with boulders
127(1)
9.10.5.5 Foundation tip integrity
128(1)
9.10.5.6 Commentary - suction pile
129(1)
9.10.5.7 Commentary - anchor chain
130(1)
9.11 Installation in sand
131(32)
9.11.1 Sand plug liquefaction, piping and heave in sand
131(3)
9.11.2 Models for sand
134(1)
9.11.3 Sand installation example
135(7)
9.11.3.1 Example - sand installation
139(3)
9.11.3.2 Commentary
142(1)
9.11.4 Friction set-up in sand
142(1)
9.11.5 Back analysis of installation data in sand
143(1)
9.11.6 Observational method in Peck (1969)
144(1)
9.11.7 Observational method in CEN (2004)
145(1)
9.11.8 General
145(1)
9.11.9 Water pocket model
146(12)
9.11.9.1 Example - water pocket model
153(5)
9.11.10 Reverse punch-through failure
158(5)
9.11.10.1 Example - reverse punch-through
160(2)
9.11.10.2 Commentary
162(1)
9.12 Installation in (weak) rock
163(8)
9.12.1 Impact driving
163(5)
9.12.1.1 Pile driving refusal
165(1)
9.12.1.2 Risk of buckling
165(3)
9.12.2 Drilling
168(3)
9.12.2.1 Drive drill drive
168(1)
9.12.2.2 Drilled and grouted
169(2)
9.12.3 Vibratory
171(1)
9.13 Presentation of installation assessment
171(1)
9.14 Retrieval and removal resistance assessments
172(1)
9.14.1 Suction foundations
172(1)
9.14.2 OWT monopiles
172(1)
9.15 Closure
173(2)
10 In-place resistance 175(66)
10.1 Introduction
175(1)
10.2 Loading conditions and soil response
175(1)
10.3 In-place failure modes
175(1)
10.4 Tension cracks and gapping
176(1)
10.5 Maximum axial resistance
176(11)
10.5.1 Failure modes for maximum axial tensile resistance
176(6)
10.5.1.1 Tensile V loads (anchor foundations) in "undrained" soil
177(3)
10.5.1.2 Compressive V loads (support foundations) in "undrained" soil
180(1)
10.5.1.3 Example - maximum axial resistance
181(1)
10.5.2 Undrained ("clay") soil response
182(1)
10.5.3 Undrained ("sand") soil response
183(1)
10.5.4 Drained ("sand") soil response
184(1)
10.5.4.1 Compressive loads
184(1)
10.5.4.2 Tensile loads
184(1)
10.5.5 Axial myths
184(11)
10.5.5.1 Bearing capacity factor Nc
184(2)
10.5.5.2 Skin friction and end-bearing
186(1)
10.6 Maximum lateral resistance (support foundations)
187(3)
10.7 Maximum lateral resistance and lug position (anchor piles)
190(4)
10.8 Maximum torsional resistance
194(1)
10.9 Tilt and twist (anchor piles)
195(2)
10.9.1 Example - twist
196(1)
10.10 Resistance under combined VHM(T) loads
197(1)
10.11 In-place resistance analysis methods
198(3)
10.11.1 General
198(1)
10.11.2 Undrained soil response (clay)
198(3)
10.11.3 Drained soil response (sand)
201(1)
10.12 VHM(T) resistance envelope methods
201(23)
10.12.1 General
201(1)
10.12.2 Undrained soil response ("clay")
201(4)
10.12.2.1 Undrained soil response ("clay")
201(3)
10.12.2.2 Example sea floor VHM loads
204(1)
10.12.3 MH ellipses
205(1)
10.12.4 V-Hmax ellipsoids
205(3)
10.12.5 VHM envelope - equations
208(1)
10.12.6 VHM envelope - yield function
208(1)
10.12.7 Modifying lateral and V max resistance
209(3)
10.12.8 Resistance comparisons
212(2)
10.12.8.1 Support foundations
212(1)
10.12.8.2 Anchor pile (and chain) foundations
212(2)
10.12.9 MH ellipse - design examples
214(2)
10.12.10 V-Hmax ellipsoid - design example
216(1)
10.12.11 VHM envelope - support foundation design example
217(3)
10.12.12 VHM envelope - anchor foundation design example
220(3)
10.12.13 Drained soil response ("sand")
223(1)
10.13 Resistance at shallow penetration
224(1)
10.14 Resistance in (weak) rock
224(11)
10.14.1 General
224(1)
10.14.2 Axial resistance of driven piles in weak rock
224(2)
10.14.3 Axial resistance of drilled and grouted piles in rock
226(6)
10.14.4 Lateral resistance in rock
232(3)
10.15 Group resistance
235(4)
10.15.1 General
235(1)
10.15.2 Considerations
235(1)
10.15.3 Design procedures
235(1)
10.15.4 Design tools
235(1)
10.15.5 Braced support groups
235(4)
10.15.5.1 Shallow foundation groups
235(3)
10.15.5.2 Anchor pile groups
238(1)
10.16 Closure
239(2)
10.16.1 Clay
239(1)
10.16.2 Sand
239(2)
11 In-place response 241(14)
11.1 Introduction
241(1)
11.2 Displacement under static loads
241(7)
11.2.1 General
241(2)
11.2.2 Immediate displacement
243(2)
11.2.3 Primary consolidation settlement
245(2)
11.2.4 Secondary compression (creep) settlement
247(1)
11.2.5 Settlement induced by cyclic loads
247(1)
11.2.6 Regional settlement
248(1)
11.3 Displacement under dynamic and cyclic loads
248(2)
11.4 Response in (weak) rock
250(3)
11.5 Closure
253(2)
12 Miscellaneous design considerations 255(20)
12.1 Introduction
255(1)
12.2 Scour protection
256(1)
12.3 Interaction with adjacent infrastructure
256(5)
12.3.1 Introduction
256(1)
12.3.2 Jack-up spudcans
257(4)
12.3.3 Adjacent intermediate foundations
261(1)
12.3.4 Adjacent shallow foundations and pipelines
261(1)
12.3.5 Conductor wells
261(1)
12.4 Shallow gas
261(1)
12.5 Permanent passive suction
262(1)
12.5.1 Example - permanent passive suction
262(1)
12.6 Top plate vent design
263(2)
12.6.1 Example - top plate vent design
264(1)
12.7 Suction pump design
265(1)
12.7.1 Example - suction pump flow rate
265(1)
12.8 Foundation instrumentation
266(1)
12.9 Steel design
267(1)
12.10 Soil reactions
267(1)
12.11 Underbase grouting
268(1)
12.12 Anchor chain trenching
269(5)
12.12.1 Commentary
274(1)
12.13 Closure
274(1)
Acronyms 275(2)
Notation 277(4)
References 281(20)
Index 301
The late Steve Kay was an independent Geotechnical Consultant with thirty-three years experience as a Principal Engineer with Fugro, and over forty-five years as a geotechnical specialist, mainly in the oil and gas industry, both with contractors and consultants. His expertise was in shallow and intermediate (caisson, bucket, can) foundation design, with extensive worldwide experience in offshore, nearshore and land engineering. He gave suction foundation courses, master classes and wrote the commercially available software package CAISSON_VHM.

Susan Gourvenec is Royal Academy of Engineering Chair in Emerging Technologies in Intelligent & Resilient Ocean Engineering, and Professor of Offshore Geotechnical Engineering at the University of Southampton, UK. Susan is currently Convenor of the International Standardisation Organisation (ISO) committee responsible for developing industry standards for marine soil investigation and offshore geotechnical design. Susan co-authored Offshore Geotechnical Engineering (CRC Press, 2011) and co-edited the proceedings of the inaugural and second International Symposia on Frontiers in Offshore Geotechnics (ISFOG).

Elisabeth Palix has eighteen years experience in offshore geotechnics. She spent twelve years working for Fugro Geoconsulting before joining EDF Renouvelables, where she is working on design and installation aspects of offshore projects. Elisabeth is also a member of the TC 209 (ISSMGE) and has been involved in several geotechnical R&D projects (e.g. SOLCYP, SOLCYP+, PISA, Unified CPT-based methods).

Etienne Alderlieste is a Senior Geotechnical Researcher/Consultant for Deltares, where he is working on installation and in-place capacity of intermediate and shallow offshore foundations. Before joining Deltares, Etienne worked as Senior Geotechnical Engineer at SPT Offshore, where he designed suction foundations for the oil, gas and offshore wind industry. He also installed and reinstalled numerous single-suction anchors and several jacket structures with suction foundations worldwide.