Análise da estabilidade intacta de navios de apoio offshore sob perspectiva da segunda geração de critérios de estabilidade da IMO

Abstract

One of the main topics of study related to the safety, comfort or operability of a floating structure is its intact stability. Currently, the rules in use are known as the first generation of stability criteria of the International Maritime Organization (IMO), which are mainly based on static considerations. However, a number of accidents related to intact stability have clearly demonstrated that stability criteria needed to be revised to address modes of failure associated with ship dynamics, especially in waves. Thus, in 2002, the IMO proposed a comprehensive review of the current criteria and opened discussions to develop a second-generation of stability criteria. The new criteria assess the vulnerability of ships in five modes of stability failure: parametric roll, pure loss of stability, broaching, dead ship condition and excessive acceleration. The present work aims to investigate and analyze these criteria for the case of an offshore support vessel, focusing on the parametric roll and pure loss of stability. For this, the DSSTAB, program developed in parallel to this work, was used, with the container carrier C11 as benchmarking. The results show that the studied PSV vessel is not vulnerable to parametric roll and pure loss of stability for the loading conditions analyzed at the first level. However, an inconsistency is found between the first and second levels of pure loss of stability.