FORCE RESULTANTS FOR DEEP-WATER WAVE-EXCITED OFFSHORE STRUCTURES

Concepts are developed which lead to an improved understanding of the characteristics of the wave forces that act on deep-water, jacket-type offshore structures. These concepts are the result of comprehensive e xaminations of both the inertia and the drag force components of the w ave excitation. It is shown that, under conditions which are of practi cal importance, the resultants of the inertia and drag force component s can both be expressed in terms of the motion of the sea surface. Fun damental modal forces which govern fundamental modal responses for off shore structures are also examined, and the relationships between thes e modal forces and the resultants of the inertia and drag force compon ents are established. The structural response itself is further examin ed, and Valuable information is developed which is believed to be of p ractical importance.