Research On Adverse Weather Warning And Transportation Security Technology Of Arterial Highways In Shaanxi Province

As an important component of the highway network,the arterial highway is an important infrastructure which can strengthen the structural and functional interconnection between urban and rural areas,and stimulate regional material and cultural communication.In recent years,traffic accidents caused by adverse meteorological conditions and geologic hazard have continued to rise,posing a huge threat to social economy,people ’s lives and property.Under this background,how to effectively analyze the characteristics and causes of past accidents so as to timely issue the information of adverse weather and design proper vehicle route guidance modes to ensure the safe and efficient service of arterial highways under adverse weather conditions has become the hot issue in this field.Based on the unique climatic conditions and accident characteristics in Shaanxi Province,the thesis conducted an in-depth study on the meteorological monitoring and warning as well as the transportation security technology of roads under adverse meteorological conditions.In view of the special geological and meteorological conditions in Shaanxi Province,the concept of vehicle route guidance for different zones was proposed according to local conditions and a related guidance system that can adapt to different adverse weather was built.The results are of great value in engineering,aiming at the safe and efficient service of the arterial highways.Specifically,the main work and results of the thesis are as follows:1.The thesis first investigated and analyzed the basic conditions of arterial highways and the climatic characteristics of different weather such as wind,fog,rain and snow in Shaanxi province,and further analyzed the mechanism and impact brought by adverse meteorological conditions on traffic safety,which was,to some degree,useful for the following research to put forward targeted strategies.2.The thesis used the road friction coefficient and visibility index to derive the formula for calculating the maximum critical speed of the following car,which simplified the impact of adverse weather on the road and proposed a dynamic speed limit management method based on the static speed limit.Under the premise of balancing economy and safety,the road closure standard could be used as a reference for road management in areas affected by adverse weather.3.Based on the analysis of the principles of path selection,the thesis adopted the optimal control model for traffic users and established traveler’s path selection model based on Binary Logit algorithm.The route selection model was then calibrated and tested.In the provided example,two characteristic variables of inherent dummy and travel time reliability were selected to construct the utility function,which proved that the model has high accuracy.4.Combined with the unique climatic characteristics in Shaanxi Province,the thesis analyzed the traffic guidance demand under adverse weather conditions,put forward the concept of vehicle route guidance for different zones,and adopted a combination of "dynamic and static" guidance facilities to build a system that can adapt to different severe weather,in which the key guidance technology for different guidance nodes and the conditions to use guidance facilities were included.Finally,the thesis took some sections of G316 national highway as the research target,based on which a simulation model was established in VISSIM.The simulation results showed that under the influence of adverse weather conditions,vehicles could be evacuated within a specified period of time,and the travel time as well as delay indicators could be more reasonable,which verified the effectiveness of the traffic guidance scheme.