Research On The Operational Limitation Based The Second Generation Intact Stability Rules Of Ships

At present,IMO is developing a second-generation intact stability criterion.The vulnerability criteria of the five failure modes are basically determined,but the operational limitation based on the second-layer evaluation and operational guidance based on the direct stability assessment.However,all world countries did not reach the conclusion about operational limitation based on the second-layer evaluation making methods,which is an urgent problem to be solved in the future.As a shipping country,if you want to have a place in international shipping,you must actively participate in the research and formulation of international standards,and can propose constructive opinions and methods.In this paper,the pure loss of stability and parametric rolling in the second-generation intact stability are taken as the research direction.The research method of the operational limitation based on the second layer of vulnerability criteria of pure loss of stability and parametric rolling is discussed.The following research is done:Firstly,develop a calculation program about the operational limitation based on the second layer check on the pure loss of stability and develop a calculation program about the operational limitation based on the second layer check on parametric rolling.Secondly,Select 500 tons of fishery vessels in Liaoning Province as sample ships,and generate dangerous sea state distribution maps based on the pure loss of stability.Select C11 container ship as a sample ship to generate dangerous sea state distribution map based on parametric rolling.Thirdly,the effects of heading,speed,draught and height of gravity on the safety of navigation about pure loss of stability and parametric rolling are analyzed separately.Based on the pure loss of stability,the operational limitation for achieving safe navigation of ships for 500 tons of fishery vessels in Liaoning Province and based on the parameter roll for the C11 container ship,the operational limitation for safe navigation of the ship is proposed.Finally,Suggestions for the improvement of the IMO calculation method for the second layer check C2 of the parametric rolling.