FEM research on bearing capacity in layered soils of spud foundation for jack-up self-elevating drilling platforms

Spud punch-though continues to be a major cause of foundation failure of offshore jack-up self-elevating drilling platform. The resulting damage range from minor structural damage of its leg and jacking mechanism to complete loss of the platform. Most punch-though failures happen during the jacking up and preloading in layered soils profiles with a relatively thin larer of sand or stiff caly overlying a weaker layer. By using FEM software ABAQUS which takes the contact interaction between spud foundation and the soil into account, the bearing capacity of spud foundation in larered soils is studied and the vertical resistance-penetration responses are analyzed. The study shows that punch-though failure is directly linked to the relative thickness of the top layer to the spud diameter and the strength ratio between the two soil layers. The paper compares the FEM results with the theoretic analysis results, good agreement is found between them, thus verifying the validity of ABAQUS FEM software in engineering design.