Safety evaluation for highway expansion and upgrading based on access management

The changes of highway condition during highway expansion and upgrading were analyzed, such as changes in the road elements, traffic operation and safety engineering facilities. Aiming at different grades of highways, the parameters describing an area where access roads were impacted were obtained from expert survey analysis of impact on the psychology and driving behavior of drivers. The parameters were then given corresponding weight. A safety evaluation model that was access-management-oriented and based on fuzzy calculation was proposed to analyses the safety situations before and after the highway expansion and upgrading. In the evaluation model, safety situations were graded. A higher score indicated a better traffic safety situation. The model was applied to a 50km-long 2nd-grade highway to be upgraded to 1st-grade in Guangxi Zhuang Autonomous Region of China. As the result showed, the score of the highway’s safety was consistent with the actual traffic operation. The proposed methods could be used to improve the design of highway expansion and upgrading in terms of traffic safety.