The first container fleet in Japan is coming into view as a part of containalization of this country.
This paper gives the result of our study on the torsional strength and rigidity which is the most serious problem in the structural design of container ship.
First, the twisting moment acting on hull was obtained in static and the values of moment were compared with those by De Wilde's or Vedeler's theory.
Second, distortion of hatch opening and nominal bending and shear stress acting on the ends of cross deck in actual ship were studied and the effect of reinforcement at cross deck, was investigated.
