Rational Design Concept for Breasting Dolphins

New deepwater ports are often designed with small operating platforms incapable of withstanding the impact of a berthing ship. These platforms are protected by breasting dolphins. Based on past studies, it is concluded that the designer may assume that one-half of the ship's kinetic energy, as calculated for a berthing velocity of 0.5 fps, will be the maximum energy to be absorbed by a single dolphin at facilities which service large vessels. It is proposed that freestanding tubular piles be used as breasting dolphins at such facilities. A scheme for accomplishing the analysis of such dolphins is presented which leads to an accurate assessment of the energy absorption characteristics of the dolphin. The paper concludes with a case study which demonstrates the analytical scheme, pointing out in particular that the computed response of a dolphin to impact is nonlinear.