ESTIMATION OF ULTIMATE LONGITUDINAL BENDING MOMENT OF SHIPS AND BOX GIRDERS

The paper describes a methodology of computing the ultimate value of t he longitudinal bending moment at any cross section of a ship or box g irder. The cross section has been discretized into stiffened panels (o ne stiffener with its associated effective plating). The limit states for these panels, both tensile and compressive, are modeled in an appr opriate manner. Since the ultimate strength of the girder section is l argely governed by the behavior of the panels under compression, the a uthors have paid special attention in modeling the collapse as well as post-collapse behavior of these panels. A new stress-strain relations hip is also introduced. The complete procedure has been coded into a F ORTRAN program and tested against a number of box girder models and an actual ship for which the true behavior was known, The results obtain ed from the proposed program appear to be quite satisfactory. Good cor relation was also found when compared with the results obtained by mor e complex and rigorous analytical methods.