The Titanic Disaster and Ice Mechanics: Completing the Picture

Abstract

Although the Titanic disaster occurred 100 years ago, explanations of the failure rely heavily on studies of the structural failure (failure of the rivets, brittle fracture of the side plate, ... for example). Very little attention has been paid to how the ice delivered the required force. Background to the disaster is reviewed and in particular the records of experiences of passengers showing that the impact involved a “slight jar” or a “little vibration”. These indicate small global loading but not excluding the possibility of high local loading. The construction of the Titanic is described, and in particular the overlapping plates connected by rivets. Evidence based on ultrasonic scans and calculations of the flow of water into the vessel suggests that the failure was associated with a series of slits in the hull, with a total area of about 12 square feet. Recent explorations into the strength of the rivets are described. The main focus of the paper is then introduced: the formation of high pressure zones in ice compressive failure. The total load in these tests may be of the order of several MN. The high-pressure zones are characterized by a localization of damage in the ice resulting in the formation of a distinct layer of microstructurally modified material. Pressures from the ramming of ice features in ship rams are analyzed, and it is again shown that forces associated with quite small areas may be of the order of several MN. When compared to the strength of the rivets, it is clear that enough force can be generated to cause slits of the kind deduced from the evidence. The results are also consistent with the observed small motions of the ship during impact. The Titanic was not designed for interaction with ice and avoidance would have been a wise course of action. It seems inappropriate to suggest that poor rivet construction was the cause of the sinking. The main cause was the high local loads involved in ice-structure interaction.