Remarkable consequences of maritime accident can be various, including structural damage, loss of life and marine pollution. During an accidental phenomenon, such as ship grounding, the amount of oil spillage indicates casualties’ extent of surrounding sea water. Effort to provide protection for sea environment against such event has been conducted actively by developing navigational instruments, and passively using structural development and assessment. The accidental grounding is, however, a very complicated process with high sensitivity to given factors during its occurrence. Variety in ship type, location, obstruction etc. affected by advance improvement in naval technology, invites sustainable analysis for structural crashworthiness and failure to produce evaluation data.
This work aims to perform an assessment on double hull tanker subjected accidental grounding with oceanic seabed as the obstruction. Fundamental concept of bottom raking is used to design grounding scenario using numerical experiment. Non-Linear Finite Element Method (NLFEM) is deployed to idealise tanker structure and obstruction geometry. The selected crashworthiness criteria in grounding are summarised to provide structural prediction in moment double hull members are experiencing crushing process. Influence of geometrical parameters’ variation to progressive failure is presented with contribution of double bottom members to structural behaviour in final part. Result data of the current work can be a reasonable reference to understanding double bottom performance in grounding, especially in raking case. Insight of such accidental phenomenon is very useful in further effort to minimise grounding consequences.
The safety of ship under collision has been developed in terms of navigational and structural aspects. These efforts are aimed to provide more safety from the internal part of a ship. However, in a collision, the external dynamics also needs to be considered, for instance velocity and location. In this study, these parameters are applied and observed regarding on a series of ship-container collision scenario. A freight container is used in the first stage and behaviours such as internal energy and effective stress are summarized. An alternative design so called buffer container is presented to offer better protection to a liquid cargo. The second stage is started by applying similar collision scenario as the first stage to the buffer container and comparing structural behaviour of this analysis. It is obtained that leakage possibility can be reduced on the buffer design as the strength has become approximately twice better than the freight container.
Unexpected loads are commonly applied in cargo ships when workers fail to comply with applicable regulations while loading and unloading cargo. This important factor can shorten the design life of a ship by increasing the possibility of structural damage. One way to improve the reliability of the fatigue life of a ship is to check for fatigue damage by observing real-time stress response depending on marine environmental conditions. Modern stress monitoring systems are installed in critical spots to capture stress signals and used to minimize the risk of crack occurrence. In the present study, a hull residual life prediction procedure was introduced by integrating traditional fatigue analysis and the stress response obtained from strain gauges installed in the hull. A three-cargo-hold oil tanker model was used to calculate the residual fatigue life using Harmonized Common Structure Rules (CSR-H). For evaluation, data obtained from the strain gauges and predicted data using a deep-learning technique were compared. According to the results, this process could be applicable to predicting residual fatigue life during a ship's operation in real time if a long period of statistical data is available. The developed techniques can help analyzing the fatigue integrity of operating ships and ship equipment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.