Technical papers

Characterization of oil well cement performance during early hydration under simulated borehole conditions

Experiments on oil well cement (OWC) slurries were performed using the newly developed laboratory-scale wellbore simulation chamber (WSC).

DOI: 10.2118/205350-PA

Seismic coefficients for simplified deepwater slope stability assessment under earthquake loading

Pseudostatic limit-equilibrium based slope stability analyses are carried out on a routine basis to evaluate stability of submarine slopes under earthquake loading. For slopes in deepwater settings, a major challenge in performing pseudostatic slope stability analyses is selection of an appropriate seismic coefficient.

DOI: 10.4043/31056-MS

Seismic attributes and acoustic inversion for shallow marine slope stratigraphy analysis

Geophysical seismic surveys have been used in marine site characterization for subsea engineering and the design of offshore structures. Signal processing plays a key role in obtaining seismic attributes from observed seismic data to identify subsurface geological features within complex shallow sediments.

DOI: 10.4043/31102-MS

Normalized modulus reduction and damping ratio curves for bay of Campeche calcareous clay to carbonate mud

Equations to calculate the modulus reduction curve (G/Gmax-γ) and material damping ratio curve (D-γ) of calcareous clay and clayey carbonate mud of the Bay of Campeche and Tabasco Coastline are developed. This was achieved using a database of 156 resonant column tests and 468 strain-controlled cyclic direct simple shear tests performed in clays with 10 % ≤ CaCO3 ≤90 %.

DOI: 10.4043/31153-MS

Experience with interface shear box testing for pipe-soil interaction assessment on sand

This paper is a companion paper to OTC 28671, titled “Experience with Interface Shear Box Testing for Axial Pipe-Soil Interaction Assessment on Soft Clay”* and presents a similar range of experience and best practice recommendations for geotechnical laboratory testing to determine soil properties relevant to pipeline-seabed friction on sandy seabeds.

DOI: 10.4043/31268-MS

Flight-test evaluation of integer ambiguity resolution enabled PPP

The technology of integer ambiguity resolution-enabled precise-point-positioning (also referred to as PPP-AR) has been proven capable of providing comparable accuracy, efficiency, and productivity to long-baseline real-time kinematic positioning (RTK) during the last decade.

DOI: 10.1061/(ASCE)SU.1943-5428.0000367

Results of a critical state line testing round robin programme

A critical state testing round robin programme was carried out on sandy silt gold tailings. This involved 15 laboratories around the world testing a sandy silt tailings to infer its critical state line (CSL).

DOI: 10.1680/jgeot.19.P.373

ANN-based decision making in station keeping for geotechnical drilling vessel

Offshore vessels (OVs) often require precise station-keeping and some vessels, for example, vessels involved in geotechnical drilling, generally use Spread Mooring (SM) or Dynamic Positioning (DP) systems. Most of these vessels are equipped with both systems to cover all ranges of water depths.

DOI: 10.3390/jmse9060596

The importance of seafloor mapping to the new blue economy: a private sector perspective

This chapter explores the importance of seafloor mapping to the new blue economy and the private sector’s role in making these critical datasets more accessible worldwide. It starts by decribing a general lack of good bathymetry data globally, and notes how this deficiency inhibits sustainable ocean development.

DOI: 10.1016/B978-0-12-821431-2.00020-2

Robotics and automation advance the offshore wind industry: increased integration of remote technology will transform maritime operations and maintenance practices

During the life cycle of offshore wind farms (OWFs), operators must maximize the uptime of wind turbines to generate as much energy as possible.