Frontiers in Offshore Geotechnics
Proceedings of the International Symposium on Frontiers in Offshore Geotechnics (IS-FOG 2005), 19-21 Sept 2005, Perth, WA, Australia

Table of Contents

Keynote papers
Suction anchors for deepwater applications
Vertically loaded plate anchors for deepwater
Australian frontiers – spudcans on the edge
Suction caissons for wind turbines
Pipeline geotechnics – state-of-the-art
An operator’s perspective on offshore risk assessment and geotechnical design in geohazard-prone areas
Offshore site investigations: new frontiers

Deepwater developments: drag and plate anchors
Influence of anchor geometry and soil properties on numerical modeling of drag anchor behavior in soft clay
The effect of interface friction on the performance of drag-in plate anchors
Proposed upper bound analysis for drag embedment anchors in soft clay
Ultimate pullout capacity of SBM’s VErtically Loaded Plate Anchor (VELPA) in deep sea sediments
Effects of long term loading on storm capacity of vertically loaded anchors
An experimental and numerical study of rate effects for plate anchors in clay
Vertical pullout behavior of plate anchors in uniform clay
Pullout capacity of circular plate anchors in double-layered clays
The use of inflatable anchors in offshore sandy soils

Deepwater developments: suction caissons
Suction caisson soil displacement during installation
Lessons learned from several suction caisson installation projects in clay
Centrifuge tests on axial capacity of suction caissons in clay
Evaluation of recovery of wall friction after penetration of skirts with laboratory and field tests
Study of sand heave formation in suction caissons using Particle Image Velocimetry (PIV)
Electrokinetic and electrochemical stabilization of caissons in calcareous sand
Vertical uplift capacity of suction caisson in clay
Capacity of suction caissons under inclined loading in normally consolidated clay
A failure surface for caisson foundations in undrained soils
Parametric finite element analyses of suction anchors
Centrifuge modelling of suction piles in clay
Establishing a model testing capability for deep water foundation systems
Reliability-based design considerations for deepwater mooring system foundations
Validation of the use of beam-column method for suction caisson design
Validation of the use of finite element method for suction caisson design

Developments in the Australian frontiers
Geotechnical interpretation for the Yolla A Platform
Preloading of drag anchors in carbonate sediments
The geotechnical performance of Deep Penetrating Anchors in calcareous sand
Seabed geotechnical characterisation with a ball penetrometer deployed from the Portable Remotely Operated Drill
Static and cyclic behavior of laterally loaded piles in calcareous sand

Foundation solutions for offshore wind turbines
Design aspects of monopiles in German offshore wind farms
Finite element modelling of horizontally loaded monopile foundations for offshore wind energy converters in Germany
Tripods with suction caissons as foundations for offshore wind turbines on sand
The tensile capacity of suction caissons in sand under rapid loading
Moment loading of caissons installed in saturated sand
The theoretical modelling of a suction caisson foundation using hyperplasticity theory

Shallow foundations: vertical bearing capacity
Bearing capacity of parallel strip footings on non-homogeneous clay
Study on bearing behaviors of foundations on multi-layer subsoil
Numerical study of shallow foundations on calcareous sand
Undrained bearing capacity of shallow foundations on structured soils
An investigation into the vertical bearing capacity of perforated mudmats

Shallow foundations: combined loading
Yield loci for shallow foundations by ‘swipe’ testing
Investigating 6 degree-of-freedom loading on shallow foundations
Single surface hardening model – a system law to describe the foundation-soil interaction
Bearing capacity of strip footings subjected to complex loading
Numerical analysis of bearing capacity of foundation under combined loading
Centrifuge tests on improving offshore foundation systems

Shallow foundations: mobile jack-up units
Extraction of jackup spudcan foundations
Numerical simulation of the breakout process of an object at the ocean bottom
Spudcan penetration in sand overlying clay
Punch-through of spudcan foundations in two-layer clay
Influence of jack-up operation adjacent to a piled structure
FE modelling of spudcan – pipeline interaction
Jack-up footing penetration and fixity analyses

Breakwater caissons and liquifaction
Performance of caisson breakwater subjected to breaking wave loads
An interaction model for seismic stability analysis of caisson type structure
Progressive ocean wave modelling in drum centrifuge
Numerical analysis of dynamic response of seabed under random wave loading

Pipelines
The performance of pipeline ploughs in layered soils
Physical and numerical modelling of lateral buckling of a pipeline in very soft clay
Bearing capacity and large penetration of a cylindrical object at shallow embedment
Stability design of untrenched pipelines – geotechnical aspects
Pipeline-seabed interaction analysis subjected to horizontal cyclic loading
A numerical model of onset of scour below offshore pipelines subject to steady currents
Arctic seabed ice gouging and large sub-gouge deformations
Model tests to simulate riser-soil interaction in touchdown point region

Capacity of piles in sand
Results from axial load tests on pipe piles in very dense sands: the EURIPIDES JIP
CPT-based design method for steel pipe piles driven in very dense silica sands compared to the Euripides pile load test results
Bearing capacity of driven piles in sand, the NGI approach
The UWA-05 method for prediction of axial capacity of driven piles in sand
An updated assessment of the ICP pile capacity procedures
A general framework for shaft resistance on displacement piles in sand
Field research into the effects of time on the shaft capacity of piles driven in sand
Design criteria for pipe piles in silica sands
Estimating the end bearing resistance of pipe piles in sand using the final filling ratio
Evaluation of end-bearing capacity of open-ended piles driven in sand from CPT data
Evaluation of end-bearing capacity of closed-ended pile in sand from cone penetration data
The influence of effective area ratio on shaft friction of displacement piles in sand
A centrifuge study of the monotonic and cyclic resistance of piles and pile groups in sand
Correlations for shaft capacity of offshore piles in sand
Axial load tests on pipe piles in very dense sands at Ras Tanajib

Piles
Bearing capacity of driven piles in clay, the NGI approach
Lateral pile design of the Ursa tension leg platform
Case study on soil plugging of open-ended steel pipe piles in Tokyo Bay
Foundation capacity of piled offshore platforms
Soil characterization for consistent reliability in the Load and Resistance
Factor Design of pile foundations
Buckling considerations in pile design
Propagation of pile tip damage during installation
One dimensional wave propagation analysis of an open-ended pipe pile with consideration of the excess pore pressure in soil plug
Simplified analysis of single pile subjected to dynamic active and passive loadings
Simplified dynamic analysis of pile group subjected to horizontal loading
Reliability analysis on axially loaded pile foundation of offshore platforms
Numerical analysis of pile axial loading test on Ryukyu calcareous sediments
A preliminary investigation into the effect of axial load on piles subjected to lateral soil movement
Modelling combined loading of piles with local interacting yield surfaces

Assessing geohazards
Assessment of the hydrate geohazard
Gas hydrates and their potential effects on deep water exploration activities
OpenSees modeling of the 3D plastic behavior of underwater slopes: achievements and limitations
3DSTAB: a history of 3D stability analysis applied in offshore geotechnics
A study of ice as an analog of methane hydrate on the basis of static shear strength
Tackling geohazards – a case study from the Turkmenistan shelf, Caspian Sea

Site investigation techniques
Deepwater geotechnical site investigation practice in the Gulf of Guinea
The origin of near-seafloor “crust zones” in deepwater
Casing mounted method used for geotechnical drilling in Lavan
Self/barge Installing Platform, SIP II: the Calder experience
Assessment of sand quality using seismic techniques at Fisherman Islands, Brisbane
Site characterization of Bootlegger Cove clay for Port of Anchorage
The geotechnical diving bell – equipment used in Brazil to perform nearshore and offshore geotechnical investigations
Conquering new frontiers in underwater cone penetration testing
Cyclic friction piezocone tests for offshore applications
Practice notes on push-in penetrometers for offshore geotechnical investigation
Comparison of cone and T-bar factors in two onshore and one offshore clay sediments
Considerations in evaluating the remoulded undrained shear strength from full flow penetrometer cycling
Well deformations at West Azeri, Caspian Sea
Borehole squeezing in soft clays

Soil characterization
Modelling the effects of structure in deep-ocean sediments
Simulating the mechanical behaviour of some calcareous soils using the Structured Cam  Clay model
Degradation of cementation for artificially cemented carbonate sands
Detection of slight cementation in offshore carbonate deposits from laboratory testing
Experimental study on cyclic pore water pressure and volumetric changes of saturated loose sands under complex stress condition
Some geotechnical specificities of Gulf of Guinea deepwater sediments
Mineralogical characteristics of the Gulf of Guinea deep water sediments
On the compressibility of deepwater sediments of the Gulf of Guinea
On the classification of Bangkok clay deposits and their compressibility
Long-term consolidation behavior of Pleistocene clays in Osaka Bay and applicability of elasto-viscoplastic one-dimensional consolidation model
Influence of salinity on soil properties
The determination of undrained shear strength and plasticity properties from quasi-static penetration tests
Influence of height and boundary conditions in simple shear tests