ABSTRACT: The mechanism of wave induced scour around large -scale offshore structures is discussed. A comparison of two types of estimation methods, the model experiment and the computation method is made. Scouring in front of the structure can be approximately estimated by both methods. The scour on the side of the structure, however, is not well simulated owing to the lack of knowledge about the Row mechanism around the structure. The two methods are complementary to each other.
INTRODUCTION Studies of scourings around offshore structures have a long history. Most of the researchers, however, have focused on such small members as jackets or pipe lines. The scour patterns around the small-scale members are related to the fonnation of two kinds of vortices: horse-shoe vortices and Karman vortices. Around a large-scale structure, where D/L>0.2 or K.C.