We are very pleased to announce that Lankelma is now able to perform fieldwork and calibrate cone penetrometers compliant with the new and rigorous ISO-22476-1:2022 (BS EN ISO 22476-1:2023) standard for the CPT titled “Electrical cone and piezocone penetration test”.
The North Sea can challenge even the most seasoned of seafarers. When weather and the sea are involved, a “straight forward – in theory” project has the potential to become complicated. So, at times like these, there’s no substitute for experience and focus on quality and safety is paramount.
This was especially true on a recent project we were part of; a flagship carbon capture and storage project in the UK spearheaded by Genesis Energies.
Genesis Energies is a market-leading consultancy company with extensive global experience in developing innovative solutions across the hydrocarbon, renewables and alternative energy sectors. In August 2022, Lankelma were selected to be part of a groundbreaking project with the Northern Endurance Partnership (NEP), the driving force behind the ambitious East Coast Cluster initiative. This landmark project aims to capture carbon dioxide (CO2) emissions from industrial facilities in Teesside and Humberside, transporting them for safe and permanent storage in an offshore storage area in the North Sea called ‘Endurance’.
Specifically, Lankelma were contracted to test two sites where subsea feed pipes from the storage facility meet the land. The data collected will help to inform the groundworks and installation for the 28” pipes carrying the carbon to the storage area. The project was split into two phases, Humberside and Teesside where Lankelma commenced nearshore drilling at Humberside from October 2022.
Although the overall project appeared to be relatively straight forward, at that time of year, location and some of the existing infrastructure along the coastlines of Humberside and Teesside (Redcar) presented some challenges. For example, the North Sea is renowned for its turbulent weather, with strong winds and swells posing a constant threat to both equipment and personnel. Lankelma needed to implement strict safety protocols and remain adaptable to ensure the safe and efficient completion of the ground investigation project.
To ensure a smooth and successful ground investigation, Lankelma were tasked to provide geophysical surveys, onshore drilling with various in-situ testing and nearshore drilling at Humberside and Teesside.
To perform nearshore drilling and testing, the Sandpiper Jack-up was deployed. Four boreholes were required along the proposed pipeline route at Humberside and similarly, five boreholes at Teesside. All boreholes and associated grab sampling were required to collect valuable samples and in-situ data up to forty-five metres below seabed.
The second phase of the project at Teesside, namely Redcar, presented its own set of challenges. The Redcar coastline is also already home to a complex network of subsea cables and high-pressure gas pipelines. This intricate web of infrastructure meant that careful planning and precise execution was required to avoid any potential damage during the drilling. To accommodate this, regular communication was maintained with all third party stakeholders prior to any boreholes being drilled.
Certain borehole locations were located near and within the surf zone along the Redcar coast, presenting a unique challenge to position the Sandpiper in waters of just 60cm. Operating at the limits of the Sandpiper’s capabilities, the team had to exercise extreme caution to avoid grounding. To overcome this, strategic use of tides, extensive marine experience and a well-equipped support tug were used to position the jack up precisely on location as intended. This careful planning and meticulous execution was essential to avoid compromising the integrity of the jack up or the accuracy of the collected data.
Samples were meticulously collected from each test site and subsequently analysed in one of our subcontracted and specialised labs. This comprehensive approach ensured that only accurate and reliable data was collected, a crucial factor for informing the Client’s decisions.
Despite these challenges, Lankelma successfully completed the seabed testing, providing required to begin laying the groundwork for the East Coast Cluster’s carbon capture and storage pipelines. This critical step enabled Genesis Energies to progress the design phase of the project.
Here’s what Kate Lilley, the Project Manager at Genesis Engineering had to say about the experience…
“Lankelma worked collaboratively with the NEP project to perform nearshore survey works at a challenging time of year in the North Sea. They were open and proactive in communication allowing us to make decisions in real time so as to maximise results. Lankelma’s site team were efficient when performing activities on site and reporting was provided in a timely manner and fulfilled requirements of the specified scope.”
If you’re interested in finding out more about our nearshore capabilities, get in touch with our Nearshore Manager, Dave Portsmouth.
Geotechnical investigations are critical for nearshore construction projects, providing valuable insights into the properties of the seabed. With the right data, these insights are used by engineers to help make informed decisions about foundation design and construction methodologies, ensuring the stability and integrity of marine structures.
Recently, we embarked on a unique project, one that deviated from the standard multi-stage approach due to an accelerated construction timeline. This project involved our Jack Up Platform (JUP) ‘Sandpiper’, and demanded a comprehensive assessment of seabed conditions.
To successfully execute this accelerated investigation, we employed a combination of Cone Penetration Testing (CPT) and Rotary-Sonic Drilling methods.
Our Nearshore Manager, David Portsmouth, provides details of the approach and insights into the challenges and opportunities the project presented.
The project was on behalf of the German Government who are looking at upgrading and expanding one of their gas storage facilities just off the coast of the Jade River in Lower Saxony, North West Germany. It was to be started and completed quickly due to a compressed construction timeline. Data from drilling and CPT were required to inform pile design and dredging operations.
CPT data provides information such as the sediment type, strength and density whereas drilling and sampling allows these sediments to be physically acquired so that the soil type and engineering parameters can be confirmed or augmented, or simply provide information not available from the CPT.
We used the Sandpiper JUP to deploy both drilling and CPT techniques. Our CPT was provided by a custom made ‘Top Push’ system that worked in unison with our dual head (sonic/rotary) sonic rig. We were tasked with testing and sampling to some 75m below seabed.
The advantage of top push over downhole CPT is that you get a continuous profile of data, whereas with downhole CPT, pushes are generally limited to either 1.5m or 3m. Depending on ground conditions, single pushes to approximately 60m are achievable in medium dense sand. If ground conditions are too dense, we simply drill out the tested sediments and push again to the desired depth or swap to our down hole CPT system.
Our dual head rig is dedicated to the Sandpiper and is always equipped with rotary and sonic drill strings, providing assurance that data can be collected to the required depth should the CPT refuse. Sampling was also specified in the contract. However, the relative quantities of rotary coreable cohesive soil and sonic drillable coarse soil was unknown, so having versatility was paramount. The versatility when drilling is paramount. It provides the Client and Lankelma with numerous options in case of unforeseen ground conditions. It also allows us to provide Class 1 samples from varying strata.
One of the issues we did have was tidal velocity, or the speed of the current when the tide turned. It was in the region of three to four knots, maybe a little bit more. The speed of the tide hindered our work as we could only move and deploy at slack tide.
In reality, it meant we had to be specific and efficient when we moved the jack up. Battling with the force of the current on our equipment took a bit of research. We had to try and direct some of that tidal flow away from the conductor casing.
We modified the conductor casing allowing us to deploy when there was still some tidal flow rather than waiting for almost zero tidal flow. A slack tide is usually about an hour, but in the Jade River, it was only about 20 minutes. The project overall went very well.
All laboratory testing and reporting is complete. The designers have everything they need to start planning and then construction. I understand that main contractors were scheduled to start piling 4-5 weeks after the site works were completed.
“Working as a client representative on board of the Sandpiper, I had good experiences with the crew and the onshore staff. The communication with the onshore staff as well as with the crew was smooth and transparent which I appreciated since it created a pleasant working atmosphere for both parties. It was clear to me that obtaining quality data was very important for Lankelma which was reflected in their detailed and qualitative data logs and reports.”
– Kevin Vivile, Project Engineer at IMDC
For more case studies like this one, head over https://www.lankelma.com/case-studies/ or book a call with one of our experts today.
As part of our commitment to the environment and sustainability, we’ve planted 600 tree saplings at our premises.
In conjunction with the Woodland Trust’s MOREwoods scheme, these trees cover 0.5 hectares of land and will create new habitats for wildlife. We’re very excited to watch this diverse woodland grow.
The combination of our lubricating module and CPT rams proved invaluable on a basement car park investigation in central London in October.
We were working for Geotechnical and Environmental Associates (GEA) and carried out a single CPT to 26m, using our lubrication module to help the cone penetrate the underlying London Clay. The team then carried out six pressuremeter tests to 20m the following day.
“The basement rams can be transported on the back of a pick-up, which enabled us to carry out testing in the low headroom car park,” said Lankelma Technical Manager Joe Hobbs, “but it was the lubricating module that really came into its own on this job.”
The lubricating module uses water to form a lubricating layer to reduce the friction between the rods and the ground. The system has proved particularly effective in London Clay, where it has enabled testing to depths of more than 40m. The design of the module means the water is distributed behind the cone and therefore has no effect on cone readings or CPT data quality.
“Typically, maximum penetration depth would be between 18-20m, with a push force of 18t, but using the lubricating module we have reached depths of 30m with just 5t of push force,” Joe said.
Matthew Penfold at GEA added: “The preliminary outputs from the CPTs were extremely useful in providing an indication of the likely depth of the base of the London Clay and the nature of the underlying Lambeth Group, which were used to help guide our subsequent intrusive works.
“Ground conditions were confirmed in a nearby cable percussion borehole, with the base of the London Clay at about 20m and the transition in the Lambeth Group, from upper clay-dominated units into very dense sand, closely matching the observed changes in cone resistance.”
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