Offshore Geotechnical Engineering
Principal Geotechnical EngineerSubsea 7
Offshore Geotechnical Engineer
What is Geotechnical Engineering?
This homepage sets out to present what is geotechnical engineering for anyone interested.
The page mainly focus on my personal interest in offshore geotechnical engineering, but will also provide the visiter with a good introduction to the subject:
what is geotechnical engineering?
Resurrection of Limit Analysis
One of my favorite geotechnical engineering methods is limit analysis.
In recent years, I have noticed that both DNVGL-RP-C212 and ISO 19901-4 2016
have update the design codes to also include limit analysis. This was not the case in the previous revisions of the design codes.
In the past they both allowed for the use of limit equilibrium and FEA as alternative to the bearing capacity equation, but limit analysis was not mentioned.
I did find it strange that limit analysis was not mentioned in the previous design codes
– especially since the Brinch Hansen version of the bearing capacity formulation is built on limit analysis.
Geotechnical Engineering at Subsea 7
At Subsea 7, I work as a Principal Geotechnical Engineer in the Stavanger office. The geotechnical team currently consists of four engineers, providing geotechnial support to both tenders and projects. Typical work tasks in the geotechnical team include:
Geotechnical Design in Subsea 7 Stavanger - Examples
One of the geotechnical teams lastest acheviements is the foundation design of the Asta Hansteen spar anchors. These have been designed inhouse with use of amongst other PLAXIS 3-D. It is believed that these may be the largest suction anchors ever installed in Norway. This LINK is to a Statoil hopepage where you can read more about the Aasta Hansteen spar anchors.
The Geotechnical Team have prepared a paper for the OTC in Houston. The paper is a lesson learned paper on the counteract design for pipeline installation complete in collaboration with COWI for the Shell Ormen Lange project. The geotechnical design is based on limit equilibrium design to determine the horizontal capacity due to the contact force from the pipeline during pipelay.
Further, COWI used both Abaqus and Flac to perform the design. The most
difficult aspect of the design was the strength variation in the soil.
We managed to complete a design which optimized the allowable seastate for installation and
avoided a rock dump campaign.
I presented the paper during OTC in session 32, Lateral Buckling and Walking and Pipe Soil Interaction.
The paper can be downloaded from the onepetro homepage:
Lessons Learned - Counter-acts Used To Install Pipelines Offshore In Very Soft Clay
University lecturer in Geotechnical Engineering
Since 2012, I have been lecturing Geotechnical Engineering (5 ECTS) at Stavanger University. The course in geotechnical engineering is for first year civil engineering students. There are approx 70 students. I have structured the course as Chalk and talk, and prefer use of practical experience from work. I strive to bring items for each session such as torevane, sedimentary roks, geotechnical reports, geotechnical soil sample tubes etc. I teach in my spare time since I am full time employed at Subsea 7.
Graduated from Aalborg University with a Ms.C in civil engineering in 2007. During my studies, I spent one semester at Griffith University in Australia where I completed a detailed analysis and examination of coastal structures and design of pile foundations which is a branch of offshore geotechnical engineering.
Offshore Geotechnical Engineering in Subsea 7
Engineering at Subsea 7
Subsea 7 engineer and deliver complex projects in the offshore industry. Each project is engineered in a project team consisting of engineers for various disciplines. Subsea 7 has adopted the matrix structure for the projects and disciplines work together. I work as Manager of the Geotechnical Team in Stavanger and we deliver support to the Projects.
Tasks as a geotechnical Engineer
As Subsea 7 mainly engineer and install risers, umbilicals, flexibles and pipelines offshore, most of my work as
a geotechnical engineer is connected with these activities. I engineer initiations systems, provide geotechnical
engineering assessment of soil conditions, design pipeline protection structures and subsea rock structures.
Geotechnical Engineer Offshore
After completion of all rock design and coordination of the rock dump campaigns on the Dong Trym project, I
was offshore on the Van Oords Nordnes in May 2010. As the only Acergy client rep on board, I was responsible for all
communication between Nordnes and Acergy, approval of the work and I managed changes in scope.
Secondment as Geotechnical Engineer at NGI
Summer of 2008, I was invited to the Norwegian Geotechnical Institute (NGI) for a two weeks secondment. The Secondment was a mutural agreement between Acergy in Stavanger and The Norwegian Geotechnical Institute. At the Norwegian Geotechnical Institute I had mentoring sessions with some of the world leading offshore geotechnical engineers and practical geotehcnical work in the NGI laboratory. For those who do not know, NGI is a/the world leading consulting house for offshore geotechnical engineering... and they know better than most what is geotechnical engineering.