A ship is essentially an indeterminate structure in which internal forces such as bending moments and shear forces may become very large at certain points of structure and many kind of stress concentrations may occur at points of discontinuity. In Section 2, the concept of stress concentrations due to internal forces and discontinuities are discussed with the aid of the finite element method. In Section 3, the feature of stress concentrations which may be classified into several types is presented, although various phenomena of stress concentrations are observed in actual ships. Finally, the question how to deal with such stress concentrations at ships' structural design is discussed.
