Research On Flexibility In Underdeveloped Region’s Arterial Highway Design

Since the reform and opening up, China’s highway construction has gained a rapid andcontinues development. However, due to the lack of highway construction funds, complextopographic and geologic conditions, high unit costs of construction, underdeveloped areashave small-scale of arterial highway network with lower design criteria, restricting the rapiddevelopment of regional economy. According to balanced regional development strategy ofthe Twelfth Five Year Plan, reconstruction of lower speed lower capacity arterial highways inunderdeveloped regions remains to be the main task for the highway transportationdepartments and agencies.Design flexibility in highway design is a designing method that makes full use of thecurrent highway design criteria and standards to accomplish the task of sustainabledevelopment of highway network.This paper analyzes the effect of socio-economic conditions, road classification,topographic, geologic and traffic conditions on the flexibility in underdeveloped region’sarterial highway design. Purposes main principles of arterial highway design in theunderdeveloped regions, studies the method of dividing the highway design interval andlinear units. Studies the highway geometric design backgrounds, introduces the possibility offlexible design. In order to gain more flexibility in highway design, this paper proposes thedesign criteria for the design speed of50km/h,70km/h,90km/h.Finally, this paper analyzes the safety problems of highways from to aspects of inherentsafety and self-explaining characteristics, studies the three major accident types and givessome practical advice to solve the safety problems.