Study On Influencing Factors And Risk Assessment Model Of Traffic Accident In V-type Undersea Tunnels

Undersea tunnel is a special form of the tunnel,which provides direct access to people and vehicles on both sides of the Strait and the Gulf.In addition to the general characteristics of mountain tunnels,because of the particularity of undersea tunnels running through the seabed,the V-shaped upstream and downhill characteristics are formed.And because of its internal sight difference,closed space,complex facilities,difficulty in rescue and evacuation,it brings potential safety hazards.Once a traffic accident occurs,not only the local traffic function is lost,but also the traffic capacity and safety of the whole undersea tunnel and its surrounding sections are affected.Therefore,the risk assessment of undersea tunnels traffic accidents and effective countermeasures are proposed to reduce the occurrence of undersea tunnel traffic accidents.This paper summarized the domestic and foreign research status related to the influencing factors and risk assessment of traffic accidents in undersea tunnels,the time,space and morphology of the traffic accident distribution characteristics of the undersea tunnel are analyzed on the basis of traffic accident data and field investigation in recent years.Using the fault tree analysis method,this paper made a qualitative analysis of the influencing factors of traffic accidents in undersea tunnels,divided the influencing factors of five aspects: human,vehicle,road,environment and management,and analysed the main risk factors of human,vehicle,road,environment and management.According to the analysis of the influencing factors of traffic accidents in undersea tunnels,a preliminary risk assessment index system of undersea tunnels is established.The weights of each evaluation index are calculated by using the expert investigation method and AHP-windows analytic hierarchy process software,the primary risk index system is optimized,and the final index system is determined according to the weight of each index.In this paper,based on the time state analysis method,the traffic accident risks evolution network model of undersea tunnel is obtained,and the coupling effect between the risk factors of traffic system is analyzed.The coupling degree calculation model of traffic accident risk of underse tunnel is established based on the catastrophe theory,and the coupling degree measurement model of multi risk factors is established based on average mutual information theory.The coupling effect between traffic accident risk factors of underse tunnel is quantified by using the two model methods at the same time.Based on the cusp catastrophe model,the process of risk state and risk evolution is analyzed.According to the state of traffic system risk,the risk level is divided by the coupling degree of traffic accident risk factors,and the traffic accident risks assessment model of undersea tunnel is established.The traffic accident risk states simulation model of undersea tunnel is constructed by using MATLAB,and the traffic accident risk of undersea tunnel is evaluated.Based on the relevant data of Jiaozhou Bay Underse Tunnel from 2016 to 2018,the reliability of the simulation model for traffic accident risk state of the underse tunnel is verified.The measures to prevent traffic accidents in undersea tunnel are putting forward.