Macro Risk Evaluation And Prevention Strategies For Local Flood Natech Event Considering Coupling

The disasters and risks faced by the human being in modern society are intertwined and involving.Natech events(natural disasters triggering or inducing industrial accidents)are increasingly threatening industrial safety,urban safety,and public safety.As an emerging source of risk from the natural environment,the damages and impacts of flood Natech events on the industrial operation and urban functioning are more and more serious for complex coupling effects between elements,gradually gaining attention and becoming an emerging issue that cannot be ignored.Researches on Natech risk are not yet able to meet the needs of considering the coupled interactions and relationships,conducting risk evaluation and prevention,as well as ensuring industrial safety at the local level.In this thesis,the risk coupling problem under the interweaving of natural,technical and social systems is focused on,aiming to achieve the goal of local flood Natech risk evaluation and control.Combining the basic accident causation theory and disaster system theory,the coupling mechanism of flood Natech event is analyzed,the coupled risk factors are extracted,and a Natech risk evaluation model is designed based on system coupling degree.This thesis provides theoretical guidance and technical support for Natech risk prevention in industrial enterprises and local governments.The main research contents of this thesis are as follows.(1)Coupled disaster-causing mechanism analysis.Historical data and typical cases were collected,and the basic characteristics of the flood Natech disasters were summarized.The two-level disaster system of flood Natech event based on disaster system theory was clarified,as well as the components of disaster-causing body,disaster-pregnant body,and disaster-bearing body in the two-level system were analyzed.Finally,the expression form of the Natech disaster-causing process based on energy transfer theory was put forward,and the mechanism of material and energy action in the disaster-causing process was analyzed.(2)Factor coupling effect analysis.Based on the DPSIR model,combined with the characteristics of macro safety risks,a coupled risk analysis model was established to elaborate the intrinsic connection between system elements and risk factors.Flood hazard,flood exposure,flood vulnerability,accident possibility,accident severity,accident sensitivity impact factors were systematically analyzed.Furthermore,their impacts on risk and the coupling effects between factors were discussed.(3)System coupling model design.The macro coupling risk evaluation index system for local flood Natech was constructed,and the index standardization and assignment method were determined.Using the network hierarchical analysis method and Super Decision software,the index system weights were determined.With the capacity coupling function,the risk coupling degree calculation formula and the coupling risk evaluation model were designed,as well as the degree of risk coupling and coupling risk level grading criteria were determined.(4)Prevention strategy and empirical application.For different subjects of local governments and industrial enterprises,combining "3E" countermeasures and "4R" strategies,Natech risk preparation and mitigation strategies and measures for local governments and enterprises were proposed.Feicheng City and Dongping County were chosen as empirical research objects.Their data were collected,processed,and analyzed to calculate the coupling degree of flood Natech risk in the two regions.The risk levels of the two regions were compared,and the corresponding countermeasures were proposed.