In Situ Site Investigation has a wealth of experience in completing both CPT testing and UXO clearance surveys in the Marine environment; working in both nearshore (less than 40m water depth) and offshore environments (greater than 40m water depth). In Situ have the capability to carry out testing from floating pontoons, jack up barges, nearshore multi-cat survey vessels, along with much larger offshore DP vessels; operating in many different environments ranging from rivers, estuary’s and lakes to the open sea or ocean. Previous projects have included port extensions in the Middle East and Southern Africa to wind farm, HVDC cable and gas pipeline projects in the North Sea, Baltic Sea, Irish Sea and Bay of Biscay. Investigations can be undertaken utilising one of our conventional top drive CPT rigs from a static barge, workboat or pontoon or using one of our specialist umbilical controlled seabed systems deployed via a multi-cat workboat or larger DP vessel. In Situ also offer CPT data interpretation, marine sample processing and subsequent geotechnical reporting services to a wide range of clients from across the marine survey sector.
In Situ currently have the capability to undertake underwater riverbed or seabed PCPT testing to an operating depth of 3000m below water level. Utilising the 4.5 tonne capacity Neptune 5000 Marine Seabed CPT Unit equipped with a digital 5cm² cone and bespoke coiled push rod system. The unit can reach up to 20m penetration depth in ideal soil conditions.
The seabed unit is easily transported by road to site and is lifted directly from a quayside onto an awaiting survey vessel. The seabed unit provides a very rapid deployment method allowing multiple CPT tests to be undertaken within a very short period of time. Each test can also be undertaken without the requirement to deploy a static marine platform or pontoon and is ideally suited for shallow water or nearshore investigations carried out via a multi-cat workboat or similar small survey vessel.
At each required test location, the CPT unit is lowered down to the seabed or riverbed from the deck of the support vessel using the onboard mounted crane, hi-ab or deck winch, additional line is then paid out allowing the vessel to hold position without moving the CPT unit while each test push is completed. Measured digital data from the cone is transferred through a control umbilical cable to the top side system control cabin on the vessel deck, allowing real time observation of the ongoing test parameters. Each test takes approximately 20 minutes to complete then the unit can be safely recovered to the vessel deck, ready to move onto the next test location.
In Situ also have the capability to undertake full force underwater riverbed or seabed PCPT testing to an operating depth of 2000m below water level. The ROSON 100 is a high-tech device for performing piezocone surveys from bed level using a 10cm² digital Icone data acquisition system with a maximum achievable thrust of 100kN. The innovative electrical hydraulic force drive wheel system pushes a pre-assembled CPT string into the seabed or riverbed, which can reach up to 10m penetration depth in ideal soil conditions, utilizing standard 36mm outside diameter rigid steel CPT rods.
Similar to the Neptune system the ROSON unit is easily transported by road to site and is lifted directly from a quayside onto an awaiting survey vessel. It also provides a very rapid deployment method allowing multiple CPT tests to be undertaken within a very short period of time. The system is ideally suited for survey operations carried out via off-shore DP or larger multi-cat survey vessels, although In Situ have previously utilised it in several shallow water nearshore environments.
In Situ SI provide specialist geotechnical support to Clients undertaking marine surveys for offshore site characterisation in relation to subsea cable and pipeline routes, offshore windfarm arrays/export cable routes and shallow foundation or anchoring systems. Our services are concentrated in several areas: • Marine sediment logging at our dedicated logging facility, based in Rotherham, South Yorkshire. The facility is equipped with two core splitters, together with core photography set-up and logging stations. Samples from both land and marine investigations are routinely processed, with soil, marine sediments and rock photographed and logged by our highly experienced team of in-house geologists. In Situ SI routinely log to the current European standards (ISO 14688 and 14689), although other national standards, e.g. ASTM, DIN and Danish, can be utilised. • Provision of geotechnical laboratory testing schedules and managing the testing program. Geotechnical and chemical testing is carried out at a UKAS accredited partner laboratory. • CPT data processing & quality control, interpretation and reporting. In Situ SI are typically sent test data direct from the survey vessel which is checked for accuracy and quality, with a draft CPT test plot emailed back to the vessel within 12 hours. Where required, rapid turnaround of CPT quality control decisions can be made and fed immediately back to the survey vessel. Final CPT data interpretation is completed at the end of the survey works, often with the benefit of core logs, which enables a full sediment description and classification to made for each CPT location, with relevant geotechnical engineering parameters being assigned. All work is carried out to the requirements of ISO 22476-1. • In Situ SI routinely provide geotechnical reports for completed marine surveys. These reports integrate the CPT and core logging results, together with laboratory testing data, to provide a geotechnical report which focusses on an interpretation of the encountered ground conditions along the survey route. Our reports fulfil the requirements of standards such as ISO 19901-8 and Norsok. Over the last 10 years, our team of geologists have worked on over 65 offshore geotechnical site investigations carried out in the North Sea, Baltic Sea, North Atlantic, Caribbean and Mediterranean Sea and have processed over 4300 CPT tests and logged over 12,000m of marine cores. Please contact firstname.lastname@example.org for more information