This paper presents an outline of a comprehensive program system developed by the authors, which includes many functions for response analysis of a wide variety of offshore structures. Typical calculated results by this system are also presented being compared with field measurements and model test data as well as calculations by the other analysis programs. Through the comparative calculations the validity and flexible applicability of the system have been confirmed and the results presented here may be valuable and useful for the designers and researchers of offshore structures.
Various analysis program packages for offshore structures have been developed by many companies and organizations in the world so far. Most of the existing program packages for floating offshore structures are composed of motion and structural analysis programs based on Hooft's method [Hooft, 1971]. In these conventIOnal program packages hydrodynamic analysis is based on the Morison equation and/or two-dimensional potential flow theory, and global structural analysis IS executed by using spatial framework model, e.g., see [Akita et al, 1978). Recent remarkable progress of electronic computers, however, has enabled three-dimensional diffraction/radiation analysis to be in practical use and to be incorporated into a conventional analysis program package. This extends the applicability of analysis program and it may become possible to take into account three-dimensional effect of hydrodynamic loading, e.g., on massive structures such as floating artificial islands and floating crane semisubmersibles, on jackups under floating conditions, and on huge-scale barges with large breadth and shallow draft or m shallow waters. We recently completed a comprehensive computer program system in order to respond to diverse analytical problems of a wide variety of offshore structures. This new system, the integrated program system for offshore structures, is abbreviated to IPOS in this paper.