# 지반의 강성특성을 고려한 지반-돌핀구조계의 동적해석

• 이진학 (한국과학기술원 토목공학과) ;
• 오세붕 (영남대학교 토목공학과) ;
• 윤정방 (한국과학기술원 토목공학과) ;
• 홍섭 (한국기계연구원 선박해양공학연구센터) ;
• 김진하 (한국기계연구원 선박해양공학연구센터)
• Published : 1998.08.01

#### Abstract

In this paper, the dynamic analysis of a dolphin system for mooring a floating structure such as barge mounted plant is studied. The characteristics of the soil-pile system are simplified by a set of equivalent spring elements at the mudline. To evaluate the equivalent spring constants, the finite difference method is used. Since the characteristics of the soil-pile system are nonlinear in case of soft foundation, the nonlinear dynamic analysis technique is needed. The Newmark $beta$ method incorporating the modified Newton-Raphson method(initial stiffness method) is used. A numerical analysis is performed on two mooring dolphin systems on soft foundation and rock foundation. In case of the rock foundation, the characteristics are found to be nearly linear, so the linear dynamic analysis may be sufficient to consider the foundation effect. But in case of soft foundation, the non-linearity of the foundation appears to be very signigicant, so the nonlinear dynamic analysis si needed.