Research On Safety Risk Assessment Of Ship Segment Lifting Technolog

Shipbuilding is one of the most important strategic industries in China,however it is also a labor-intensive industry.Poor operating condition,huge scale product,long construction period,severe pollution to the environment and high risk have always been the main factors of accidents,such as scaffold collapse accidents,electric shock accidents,forklift truck rolling accidents,falling accidents and lifting accidents,among which lifting accidents are the most common.The most common method of modern shipbuilding is the hull block construction method,which means that parts and components in the rack are combined and welded into hull blocks,and then hull blocks will be assembled into the whole ship on the slipway.Hull block,as the most basic part,plays a significant role in ship building process.During the construction of hull blocks,lifting operation is a key and core part.In order to ensure the safe production,it is of great significance to evaluate and study the safety risk of hull block lifting operation systematically and scientifically.This paper takes the safety of hull block lifting as the research object.The main contents of the study are as follows:First of all,the research status from domestic and foreign fields is summarized,and the progress in safety of sublevel lifting from domestic and foreign experts is briefly introduced.Through the introduction of the characteristics and classification of hull block lifting,guided by the theory of safety risk assessment,combined with the construction and hull block lifting procedure,we summed up five main types of accidents in hull block lifting operation,which are the accidents of crane overturning,block falling,block squeeze and collision,crane arms bending and cracking and block deformation respectively.Then,the hazard sources of hull block lifting process are identified and analyzed by using accident tree analysis method,and the safety accident tree model of hull block lifting is established.By analyzing the basic events of accident tree model,the risk evaluation index system containing5 first level risk factors,19 second level risk factors and 57 risk factors is established.Finally,through the study of LEC evaluation method,Analytic Hierarchy Process(AHP)and Bayesian network method(BN),the safety risk evaluation model of ship lifting process combined with AHP-BN is established,and the model is quantitatively and qualitatively evaluated.According to the case of 62 B block lifting operation from dredger project under construction in shipyard,the established comprehensive safety risk evaluation model is used to evaluate the safety risk of 62 B block lifting operation,so as to verify the feasibility of the established model and to provide references for the similar hull block safety lifting.And the outcome of risk assessment is normally safe level.