LAUSR

Abstract In the present paper, the 100-year history of break-in-two accidents is reviewed considering the technological developments relevant to these events. The chronology starts from the epoch making break-in-two accident of torpedo-boat destroyer “Cobra” (1901), where Biles (1905) examined the elastic stress and deformation induced in a ship hull by hogging and sagging conditions based on the experiments using a destroyer ”Wolf,” while the ultimate bending strength was experimentally investigated by Kell (1931, 1940) using two destroyers. Then, we shall proceed to review the brittle fracture of all-welded ships during the World War II, and serious damages of bulk carriers and ore carriers experienced from the late 60s to the early 80s. In the 90s, another problem “substandard ships” had emerged, which had lead IACS to make the so-called “Common Structural Rules (CSRs)” for oil tankers and bulk carriers, while IMO implemented “Goal Based Standards (GBSs)” for new construction of oil tankers and bulk carriers in SOLAS conventions. Lastly, we shall consider the break-in-two accidents of large container ships, where discussions are made how to investigate the causes of the accidents by using the numerical tools for the evaluation of wave-induced loads and ultimate strength. Having reviewed the chronology, one may understand what have been learned in the last 100 years, and also what to be further studied in the structural design against ultimate hull-girder failures in the future.