The modern design of steel structures uses limit states classified into four types, namely, serviceability limit state, ultimate limit state, fatigue limit state and accidental limit state. The aim of this paper is to propose and illustrate a procedure to assess the capability of a spherical-type LNG (Liquid Natural Gas) carrier of 135000 m(exp3) to resist ship collisions. An assessment procedure based on the energy dissipation capability relating to structural crashworthiness can, in this case, be applied to protect spherical LNG cargo tanks from fracture in minor or moderate collision accidents as shown in the paper. In the procedures developed, while the loss of kinetic energy during the collision accident is approximately estimated by applying the momentum librium of the two implicated ships, a series of relatively sophisticated numerical computations is undertaken to simulate the structural crashworthiness of the object ship in the full load condition at standstill, varying the loading conditions and types of the striking ship, when the LNG carrier side structure is considered to be struck by the bow of either a VLCC(Very Large Crude Carrier) or another LNG carrier. Based on the computed results, the collision resistance indices (CRI), which in the present study are defined as a function of the ratio of the structural energy dissipation capability to the initial kinetic energy loss, are calculated for the object ship for various collision scenarios. Some important insights useful for preventing collision damage of the spherical LNG cargo tanks of the ship are also discussed.
Predicting resistance of spherical-type LNG carrier structures to ship collisions
Vorhersage der Widerstandsfähigkeit von Kugeltankkonstruktionen von Flüssiggas-Tankschiffen gegenüber Schiffskollisionen
Marine Technology and Sname News ; 39 , 2 ; 86-94
2002
9 Seiten, 16 Bilder, 3 Tabellen, 10 Quellen
Aufsatz (Zeitschrift)
Englisch
Predicting Resistance of Spherical-Type LNG Carrier Structures to Ship Collisions
Online Contents | 2002
|Study on side structure resistance to ship-ship collisions
Taylor & Francis Verlag | 2007
|Study on side structure resistance to ship-ship collisions
Online Contents | 2007
|Engineering Index Backfile | 1935
|