Research On Safety Evaluation Technology Of Urban Road Network Travel Route Based On Conflict

With the continuous improvement of the level of urban modernization,the urban transportation system has become increasingly perfect.Meanwhile,the urban road network has become more complex,the number of road traffic accidents is increasing year by year,and 1.35 million people are killed by road traffic every year.Faced with the severe traffic safety situation,the existing studies rarely consider and deal with safety problems from the perspective of road network travel route.Therefore,this study takes the urban road network travel route as the research object,focuses on safety issues,and on the basis of in-depth exploration and quantification of the relationship between traffic risk factors of route components and the safety level of travel route,attempts to construct a set of scientific,reasonable and effective travel route safety estimation(TRSE)method for urban road network,evaluate the safety of alternative travel routes,guide people to make decisions on safer routes and reduce travel safety risks.According to the research idea of "method construction-method application-method extension".Firstly,based on the classic safety evaluation model,safety risk(conflict rate)and risk exposure are selected to jointly represent road safety.Safety evaluation models are constructed for segments and turnings in the route respectively,and the route safety risk level is output by fuzzy logic algorithm.Secondly,based on the real road network in Changsha City,Hunan Province,the VISSIM simulation road network is constructed.After simulation calibration and validation,18 routes between 6 Origins and destinations(O-D)in the road network are selected to carry out the specific application of TRSE method.The effectiveness of TRSE method is verified by evaluating,displaying and analyzing the route safety level of peak period and off-peak period.Finally,in order to realize the advance perception of the safety level of travel route,this study constructs a vector autoregressive model based on the time series characteristics of traffic flow for short-term traffic flow prediction.Combined the static characteristics of road and the predicted dynamic traffic flow features,and relying on the TRSE method to predict the safety level of travel route.As the basic research of travel route safety,this study provides a methodological support for the development of road safety risk active management and control system.