Finishing up the week – About Residual Curvature, Convergence, and Uneven Seabeds!

Written by Martin Teigen.

I don’t know where the week has gone! I guess I am always busy, but there were many things happening this week in particular.

I finally got to issue the follow-on engineering report that I mentioned last week. This project has residual curvature and pipe in pipe.

“Finishing” one project, I was due to start on another task on 1 October where I will perform a Trawl-Pullover SRA (Structural Reliability Analysis) for another pipeline (PIP) installed with residual curvature. Exciting stuff!

What made me very busy was the fact that I also assisted in establishing a global buckling and expansion model for that same project, and gee, there were so many convergence problems! The seabed is extremely uneven, something similar to the example in the illustration below, but worse. We are talking about a 50 m height difference over 10 km of pipe, and many local extremities as well. This causes difficulties in laying down the pipeline on the seabed due to the large geometrical non-linearites.

The illustration is a example snapshot from my ABAQUS pre-processor that I made a few years back, and I basically adopted that technique in laying the pipeline down on the seabed.

Earlier in the week we got chocolates at work. They look simple, but they were actually nice!

And true to the tradition, I finished off the week with an 8 km run, which fit perfectly in with some ABAQUS test-runs.

It is 9:10 PM and I am due to go home, but I just need to start a few runs that I can check on tomorrow.

Anyways, thanks for reading, and have a nice weekend!