S12  Impacto em Estruturas    Titulo: RESIDUAL STRENGHT OF SEMI-SUBMERSIBLE PLATFORMS CYLINDRICAL DAMAGED COLUMNS   Resumo : WE`VE INVESTIGATED THE ULTIMATE LONGITUDINAL STRENGTH AND POST-COLLAPSE BEHAVIOUR OF DAMAGED COLUMNS, DUE TO IMPACT OF SUPPLY-BOATS. WE´VE RESTRICTED THE SCOPE TO INTERNALLY RING STIFFENED COLUMNS, WITH THE RATIOS RADIUS TO THICKNESS (R/T) AND RING SPACING TO RADIUS (L/R), TYPICAL OF SEMI-SUBMERSIBLE FLOATING UNITS, SUBMITTED TO LONGITUDINAL COMPRESSIVE LOADING. WE´VE CONSIDERED KNOWN THE GEOMETRICAL PARAMETERS OF THE DAMAGE (INDENTATION), SUCH AS MAXIMUM DEPTH AND AFFECTED AREA, AND INTER-RING RESTRICTED. WE´VE PERFORMED THE ELASTO-PLASTIC BUCKLING INVESTIGATION USING AN FINITE ELEMENT NUMERICAL MODEL, CONSIDERING NON-LINEAR GEOMETRIC AND MATERIAL PLASTICITY. WE´VE SIMULATED THE INDENTATION AND THE LONGITUDINAL COMPRESSIVE LOADING BY AN DISPLACEMENT-CONTROLLED SCHEME, TO AVOID NUMERICAL INSTABILITY NEAR THE ULTIMATE LOAD. WE´VE VALIDATED THE NUMERICAL MODEL BY COMPARISON TO PREVIOUS AVAILABLE EXPERIMENTAL RESULTS, AND CARRIED-OUT AN PARAMETRIC STUDY TO INVESTIGATE THE INFLUENCE OF THE FOLLOWING VARIABLES ON THE ULTIMATE STRENGTH OF THE NUMERICAL MODEL: INITIAL IMPERFECTION DISTRIBUTION, DEPTH AND AFFECTED AREA BY INDENTATION, AND THE MAGNITUDE OF THE EXISTING LONGITUDINAL COMPRESSIVE LOADING PRIOR THE DAMAGE. KEY-WORDS: SHELLS, BUCKLING, COLUMNS.     Autores : CYRINO, JÚLIO C. R. VILAIN, LEONARDO 0     Trabalho Completo :   COBEM99 | Comissão  Organizadora | Palestras | Sessões Técnicas | Autor | Simpósios e Sessões Especiais | Revisores |  Título  dos  Trabalhos | Local