Internal Angle of friction of Seabed Material

[paudie09]

Hi, im looking at a steel gravity structure that is resting on a seabed. I was wondering is there any papers reviewing appropriate friction angles of seabed floors. Sliding resistance will be a feature of the design and im trying to estimate a coefficient of friction of the base to the seabed floor (u). My horizontal resistance due to friction would then be R = F.u