The Research And Evaluation Of The Residual Strength For The Damaged Ship

A ship in navigation may happen to accidents of grounding or collision. To avoid disastrous consequences such as totally loss of the ship and subsequent pollution to environment, it is necessary to know and assess the residual strength of the damaged ship. So we can take correct technical measure to salvage, rescue and tow the damaged ship. There are only some commence works on the calculation and assessment method for damaged ships nowadays. Because the damaged ship is in the abnormal loading condition, the safety assessment should be based on its residual strength.In this paper, taking a real ship as example, the residual strength for the damaged ship is analyzed by use of the COMPASS and ANSYS software, the steps of calculation is as follows:1) The damage during the construction and navigation is categorized. COMPASS is used to establish the geometric shape of the hull to calculate various parameters of floating state, obtaining the buoyancy curve, therefore the loadings upon the damaged ship could be evaluated.2)This paper has described the relationship between the ultimate bending moment and the strain of the hull and the method called arc-length which is used in nonlinear FE Analyses. As the follows, the ultimate bending moment of the hold is calculated by the nonlinear FE analyses software-ANSYS.3)According to the Rules and Regulations of Construction for Steel Ships in Inland River of CCS the hull design load is obtained, and the residual strength of damaged ship is assessed in light of the indicators of residual strength under different damaged conditions.4)Summarize the analysis work and put forward suggestions.To ships in different damaged floating situation, the calculation method, results and conclusion are useful in drawing up the rules and regulations relating ship safety, assessing the residual strength of the damaged ships under the situation of collision and grounding.