Research On The Safety Risk Of Navigation During Vessel Towing In Yantai Port

In response to the huge pressure brought by the fierce competition in the global shipbuilding market,the major shipyards began to complement each other and cooperate in shipbuilding.Its advantage that it can save construction cost and shorten construction period for shipowner.The way to cooperate in building a ship can be that one party is responsible for building the hull and the other party is responsible for installing equipment;or it can be that many parties build the hull in sections,and then gather the sections together.It is inevitable for these projects to use the port waters where the shipyard is located for vessel towing.In the course of towing,the navigation environment of the working waters will be affected to some extent,and the navigation conditions of the waters will be changed.At present,there are some problems in the port towage navigation evaluation report,such as unclear priority of safety factors,no specific analysis of the difficulty of risk control of various safety factors and so on.It is impossible to choose a scientific and reasonable accident control plan for the implementation of port towing project.Therefore,it is necessary to establish a scientific and practical mathematical model for the port's vessel towing project,and to obtain a reasonable risk prevention and control scheme through calculation and analysis.There are few research results on the safety risk of port towing at home and abroad,most of which are qualitative analysis based on formula and experience,few quantitative analysis and complex methods,which are not suitable for the practical application of port towing project.In this paper,combined with the actual operation of Yantai Port shipyard,by comparing several commonly used theoretical methods of safety risk assessment of water navigation,it is determined to introduce a simple,reliable and easy to use FTA-AHP method to study on the safety risk of navigation during vessel towing in Yantai port.Based on the statistics of natural environment,port environment,traffic environment and traffic accidents in the waters under the jurisdiction of Yantai port,combined with expert consultation,fault tree analysis(FTA)is used to establish the fault tree of the safety risk of navigation during vessel towing in Yantai port.The basic events of the fault tree are qualitatively analyzed and the structural importance is obtained.Due to the lack of failure rate of each basic event in the fault tree of the safety risk of navigation during vessel towing in Yantai port,it is impossible to accurately calculate the probability importance of each basic event.Therefore,the basic events of the fault tree of the safety risk of navigation during vessel towing in Yantai port are classified and sorted out again,and the analytic hierarchy process(AHP)model of the vessel towing navigation safety risk in Yantai port is established.Using AHP and 59K bulk ship towing case,the basic event of fault tree is calculated quantitatively to get the total rank of risk factors.The FTA-AHP method is used to verify the analysis,and the results of risk assessment are obtained,and the pre-control suggestions for risk factors are put forward.Compared with the actual evaluation report of 59K bulk ship towing case,the conclusion of FTA-AHP is more clear and reasonable.The qualitative and quantitative analysis of Yantai port's vessel towage is carried out by using FTA-AHP method,and verified by an example.The conclusion can provide the basis of accident prevention for the navigation safety report of Yantai port's vessel towage engineering,and provides reference for shipbuilding enterprises,ports and maritime management agencies.The research results have guiding significance to avoid the occurrence of the safety accidents of the vessel towing in Yantai port.