Open AccessCase study on advanced 3D finite element limit analysis of counter-acts installed at Ormen Lange
Author(s) -
Christian Linde Olsen,
K. Krabbenhøft
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1201/1/012009
Subject(s) - finite element method , limit (mathematics) , limit analysis , base (topology) , pipeline (software) , finite element limit analysis , element (criminal law) , structural engineering , field (mathematics) , computer science , mechanical engineering , engineering , mathematics , mixed finite element method , law , mathematical analysis , pure mathematics , political science
The design of counter-acts for the Ormen Lange Northern Field Development has previously been considered in other publications. Counter-acts were used to ensure pipeline stability during pipe-lay along route curves. The counter-acts were large diameter steel cylinders installed with self-weight penetration. The in-place design was completed with use of advanced Finite Element Analysis (FEA) program Abaqus and validated in parallel by the finite difference (FD) program, FLAC. This paper will present a comparison of the previous work to advanced 3D Finite Element Limit Analysis (FELA) with use of the software OPTUM G3. 3D FELA is newly developed for geotechnical design. The paper will show the advantage of the FELA which is based on the principles of limit analysis. The counter-act design is particularly complex and given the cylindrical shape with no internal base plate. This will challenge the element types in the FELA model. Further, the soil conditions are amongst the softest clay encountered in Norway further increasing the complexity of the design.