On-Bottom stability analysis ensures the underwater piping system remain on the seabed during the operation. It is one of the important aspect in designing an offshore pipeline system. There are few methods to maintain on bottom stability, such as, trenching, pipe burial, and increase the thickness of concrete coating. On-bottom stability can be divided in, vertical stability and dynamic lateral stability.
A pipeline, if subjected to compressive normal stresses most frequently fails by loss of stability. The buckling phenomena can be distinguished in three basic modes 1) local, 2) distortional, and 3) global buckling.
Global buckling is a buckling mode where the member deforms with no change in its cross-sectional shape.
Analytical methods for the calculation of the buckling load either do not exist, or are too limited in their applicability to provide a general tool. The numerical methods such as Finite Element Analysis are considered for buckling load calculation.