BIFURCATION OF STATIC EQUILIBRIUM OF A SEMISUBMERSIBLE IN WAVES

This paper reviews the phenomenon of the steady tilt of a semisubmersi ble from the point of view of the theory of bifurcation. The problem i s similar to that of the buckling of an elastic structure, with the wa ve amplitude playing the role of the critical load. Depending on the w avenumber, the bifurcation can be ''subtle,'' as in the case of a Eule r beam, or ''catastrophic,'' as in the case of shells and arches. Expe rimental results on a simplified submerged structure show very good ag reement with the theoretical prediction from the viewpoint of second-o rder wave theory.