An analytical solution procedure that can estimate the ultimate inclined loading capacity of suction piles is described. The solution utilizes the concept of the failure envelope defined by the combined horizontal and vertical loads that cause the failure of soil. The ultimate inclined loading capacity is then described as a combination of the horizontal and vertical components that are expressed as fractions of their respective ultimate capacities.
This paper describes an analytical solution procedure that can estimate the ultimate capacity of suction piles against inclined loads. Inclined loading condition may occur when the superstructure founded on top of the suction pile is under wave action or when the suction pile is used to provide anchorage for mooring lines. The solution method utilizes the concept of the failure envelope defined by the combined horizontal and vertical loads that cause the failure of soil surrounding the suction pile. The ultimate inclined loading capacity is then described as a combination of the horizontal and vertical components, which in turn are expressed as fractions of their respective ultimate capacities. The ultimate horizontal capacity of suction piles takes into consideration the truly three-dimensional behaviors (Bang and Cho, 2001b). It considers the development of three dimensional normal and shear stresses along the circumference of the pile surface as well as a three-dimensional soil failure wedge. The ultimate vertical capacity of suction piles has been obtained by considering three possible soil failure mechanisms (Bang and Cho, 2001a). They include (1) the local tension failure which occurs when the pile and the soil inside are pulled out simultaneously, (2) the pile pull-out failure which occurs when the pile slips out of the soil, and (3) the general soil shear failure which occurs when the surrounding soil experiences failure due to tension.
