Study On The System Of Risk Assessment And The Shortest Weighted Path Selection Of Hazardous Material Transport

With the high growth of China's economy and technical revolution, the demand of hazardous material is increasing year by year. While the road transport play the most important role in hazardous material transport. However, the study about the transport of hazardous material has yet to be further developed in China.This paper explores the road transport of hazardous material by applying the risk assessment system and the route choice model. First of all, according to three features " comprehensive road safety factors-Enterprise Security Management-Transport material", the effects of several factors on the importance of safety transport are compared by the classical method. Then the weighted values are calculated based on the analysis above. The membership function in fuzzy mathematics is employed to analyze the relationship between the actual impact on road transport factors and the membership degree of the safety for transport objectives. The hazardous materials transportation safety index (HTSI) measures the security of the transportation. HTSI is accumulated the product of the weighted value of index system and the degree of membership value of the security factors.Second, according to NFPA704, the risk levels of hazardous material is determined, the weights of the major influence factors of the road route selection, such as the inherent characteristics of the road, meteorological condition, traffic condition, population distribution, injury and death rate of accident, preventive measures and the length of road section are determined. Based on decision analysis, the method of standardization is used to calculate the specific factors'parameters belonging to corresponding major factors. The length of road section is confirmed by weighting major factors, the bidirectional bound search algorithm is adopted to find optimal path out. Several factors are taken into account for transporting the hazardous material, and an improved algorithm based on Dijkstra method is applied to find out the optimal route. Finally, the given example shows that the proposed model of risk assessment is applicable and the improved algorithm is effective.