From concept and FEED through to detailed design and installation support, Xodus Subsea provides guidance for engineering developments within the oil and gas and renewables sectors.

Xodus Subsea supports engineering that demands interaction with ground conditions at a site for on and offshore developments: structural foundation design, scoping and supporting offshore site investigation surveys, pipeline/cable routing studies, pipe soil interaction design, and package management delivery for installation. We use our knowledge and experience of integrated production modelling to define the options that maximise recovery and achieve the best value solution. 

Project management of geotechnical analysis
Our expert engineers review all available geotechnical, geophysical and geological project data and decide how it should best be used to develop a ground model for a site. This review determines whether further site specific information is needed to help the design and installation process, and it identifies what risks and hazards should be avoided and mitigated for a safe and successful installation. We interact directly with project teams and manage specialist subcontractors’ (e.g. survey contractors) activities both onshore and offshore. Our geotechnical expertise is based on the delivery of multiple oil and gas and renewables projects including wind and tidal energy developments. 

Foundation design
Xodus Subsea’s geotechnical specialists assess and select appropriate foundation design solutions for subsea structures. This process includes gravity-based design, pile design, suction can assessment, spudcan analysis and other systems that require a more specialist design approach (e.g. pins, soil nails, rock dowels). Foundation design is heavily based on the soil data available. Where appropriate, we identify specific data and site investigation techniques that will meet the design requirements of the installation.

Management of offshore survey acquisition
We manage survey subcontractor packages where seabed and soil data for design analysis and seabed or site risk assessments are required. Typically, offshore surveys are commissioned using geophysical and shallow geotechnical techniques for pipeline and umbilical/cable routes, e.g. Cone Penetration Testing (CPT) and subsea structure design and installation, e.g. deeper borehole information. Onshore surveys include site walkovers and liaison with construction contractors to develop a geotechnical appraisal of a site.

Survey packages can be managed in-house and cover:

  • Preparation of tender documents
  • Review of vendor proposals
  • Managing mobilisation and offshore works from the beach
  • Sourcing offshore representatives
  • Liaising with survey contractors during the onshore test campaign
  • Ensuring all deliverables are technically compliant and satisfy project requirements.
  • Submarine pipelines/cable routing and installation

For seabed evaluations of pipeline/cable routes and assessment of landfall options, Xodus Subsea provides:

  • Geotechnical route data and design parameter assessment for hazards and cable design calculations for on-bottom stability evaluation
  • Reviews of geophysical and geotechnical seabed data to understand a site’s ground model
  • A Scope of Work (SoW) for survey site investigation including survey package management
  • Ongoing management of all available seabed interaction techniques for further cable burial and specific protection at connection points
  • Client support or provision of an offshore representative during a project’s operational phases
  • Landfall evaluations at selected sites (or help selecting a suitable site) for pipeline and cable feasibility assessments.