Στην παρούσα εργασία αναπτύσσεται η μεθοδολογία για την εκτίμηση της πιθανότητας εμφάνισης αστάθειας υπό την επίδραση κυματισμών και ανέμου χρησιμοποιώντας τα οφέλη της προσδιοριστικής ανάλυσης σε οτι αφορά την μορφή της αστάθειας και την απόκριση του πλοίου σε συνδυασμό με την πιθανοθεωρητική ανάλυση των συνθηκών περιβάλλοντος υπηρεσίας του πλοίου.
The present thesis is a development of the probabilistic method for the assessment of instability occurrence proposed by Themelis & Spyrou (2007). The core idea of the original method is that “the probability of occurrence of some instability event could be assumed as equal to the probability of encountering the critical wave groups that generate this instability”. Based on that the task could be disassembled into two parts: a mainly deterministic one, for the specification of the critical wave groups with the combined use of deterministic and analytical tools from ship motion dynamics a purely probabilistic, using statistical wave models , in order to calculate the probability to encounter these critical wave groups. The contribution of the present thesis in the original method is the introduction of the wind effect in the specification of the critical wane groups as well as the probabilistic calculation of wind force. Furthermore, long-term probabilities describing the wave climate of the ship’s service area, are taken into account in the proposed methodology assessment.