Geotechnical Services

Overview

S³’s Offshore Geotechnical Division is able to offer clients, in both oil and gas and renewable sectors, geotechnical site investigation services from shallow to deepwater environments with the acquisition of high quality engineering grade soils data for the purpose of foundation design (installation, operation and decommissioning) and cable and pipeline design and installation.

Onshore laboratory testing is offered via cooperation agreement(s) with established third-party service provider(s).

Resources

Seabed Equipment

S³ is able to offer access to a range of sampling tools, such as piston corers, box corers and vibrocorers, and in-situ tests comprising PCPT and vane shear, dependant on the nature of the sediments and client requirements.

The modular Triton XLS allows flexibility of installation layout and efficient mobilisation.

All field operations are conducted in accordance with our procedures. At all times the Client’s specifications would be adhered to, unless they are exceeded by Specialist Subsea’s own procedures.

Onboard Geotechnical Testing and Reporting

Onboard geotechnical testing and reporting would be undertaken from a containerised laboratory, providing a range of basic geotechnical parameters such as:

• Hydraulic sample extrusion and photography;
• Moisture content;
• Wet and dry density;
• Undrained shear strength, by means of:
  • Pocket penetrometer, Torvane;
  • Laboratory (motorised) minivane, Swedish fall cone;
  • Unconsolidated, undrained (UU) triaxial compression test.
• Offshore operations and preliminary laboratory reporting, plus JU rig analysis.

Soil descriptions and classifications would be made in accordance with recognised and relevant standards for site investigation and soil testing, such as ASTM (D2487), BS (5930) or Norsk Standard (NS 8000 series), with the classification system being selected in conjunction with the client prior to commencement of operations.

In-situ test data (PCPT and vane) would be processed shortly after the test is performed with preliminary results normally being available within 24 hrs of the test.

At demobilisation, the onboard client representative would be provided with preliminary in-situ test data and preliminary borehole logs.

Onshore Geotechnical Laboratory Testing and Reporting

If required, onshore laboratory testing and preparation of factual as well as parameters and engineering reports are subcontracted to an established third-party service provider, selected in accordance with client preference. Where possible, a number of the laboratory personnel are utilised offshore, to facilitate the reporting effort and to ensure smooth transition of samples and data between offshore and onshore sites.

In the onshore laboratory, cores are split, described, logged and tested in accordance with client’s requirements and/or a mutually agreed testing schedule. The remaining sample would be resealed in the core liner or bagged for storage.