The geotechnical department within Aqualis is primarily based in the UK and is led by the subsidiary renewables company Offshore Wind Consultants Ltd (OWC). The team consists of engineers who have many years of experience within the offshore industry and possess both excellent design and analytical skills combined with direct experience of working offshore. Our staff are specialists in jack-up leg penetration analyses, offshore site investigations, and geotechnical design and installation analysis for offshore oil and gas and wind turbine foundations.
Jack-up Leg Penetration Analyses
We are experienced in jack-up drilling rig leg penetration analyses and have developed bespoke software to predict spudcan penetrations using the latest relevant codes and standards. The calculation assesses the spudcan capacity considering layered soils and identifies risks such as rapid leg penetration and punch through. Based on the penetration prediction, we either undertake leg extraction analysis or scour studies to further understand relevant risks. We have undertaken analyses for soils worldwide.
We have access to and use a large and increasing database of previous loading and penetrations to constantly optimise our analyses.
The penetrations, fixities and V-H envelopes determined by the geotechnical team are then used by our structural engineering team in their Site Specific Assessments.
Aqualis, through their renewables subsidiary OWC are very experienced at offshore wind farm Site Investigation (SI) management, with staff who have managed many SIs over the last 10 years. Our capabilities span the whole life cycle of the SI process, and include:
- Running SI tender competitions
- SI scoping and contractor management
- Onshore project management during the SI
- Scheduling of onshore/offshore laboratory and in-situ testing
- Provision of experienced offshore Client Representatives
- Use of live SI methodology tool (i.e. calculating the length of borehole required as the ground information is gathered, ensuring boreholes are economically sized) for which we were finalists at the Ground Engineering 2015 awards
- Data interpretation and development of final soil models for foundation and cable design using SI data and preparation of Geotechnical Interpretative Report
- Assurance that regulatory and certification authority requirements are met
Ground Modelling & Geotechnical Interpretation
Our team have developed ground models for the world’s largest and most complicated offshore wind farm sites. We utilise advanced software to manage and interpret large data sets of ground investigation results to:
- Identify engineering units across a site
- Understand expected ground behaviour
- Develop geotechnical design parameters
- Identify and manage ground based risks
- Assess lateral and vertical ground variability
We also work closely with geophysicists to produce a ground model benefiting from the advantages of both geotechnical and seismic assessments.
Our geotechnical engineers have designed over 500 offshore wind farm foundations, and are experienced at:
- Development of design soil models
- Finite Element Modelling
- Selection of geotechnical parameters
We have designed monopiles, jacket piles, gravity bases, mat foundations, ground anchors and suction caissons. We use the latest standards, industry research and best practice to ensure that our designs are safe, efficient, reliable and satisfy latest code and certification requirements.
Our team utilises a life-cycle approach to identify possible design issues early in the ground model process and mitigate the risks through improved site investigation methods and design studies.
Foundation Installation Analysis
Following foundation design our geotechnical engineers often undertake the installation analysis and management, this includes:
- Pile driveability assessments
- Site supervision during foundation installation
- Pile driving induced fatigue analysis
- Seabed preparation advice
- Mudmat design
Cable Route Analysis and Planning
We have wide ranging experience in the design and management of cable routes to ensure the effective protection of the cable system throughout its design life. We have our own in-house cable experts and consultants who work closely with our in-house geotechnical team. The team can review the available information such as SI, bathymetry, seabed mobility and other hazards to prepare burial risk assessments and assess the expected performance of available installation tools.