Study on Quantitative Evaluation of Control Information of Expressway Guide Sign Based on Network Toll Collection Data Analysis

Expressway guide sign is important for traffic safety. The selection of control information of expressway guide sign has a strong impact on the effectiveness of expressway guide sign. Most of the previous studies on the evaluation of control information of expressway guide sign are aimed at qualitative analysis or quantitative analysis without considering the data of operating period, especially the network toll collection data. So some systematic investigation and analysis work are completed using the network toll collection data collected from Guangxi Zhuang Autonomous Region in China. The useful data are abstracted and the calculation method of cross-sectional traffic volume is provided. Based on these analyses, the concept of traffic gravitation is proposed and model of traffic gravitation between two cities is built which considers the factor of distance, the factor of cross-sectional traffic volume, and the factor of regional differences in China. The value of traffic gravitation can be calculated by the model of traffic gravitation. By comparison of the value of traffic gravitation among different control information, the control information whose traffic gravitation value is largest can be selected as the right control information. In this way, the present control information can also be evaluated. The flow chart of evaluation of control information of expressway guide sign is also provided. This quantitative evaluation method has already been used for road safety evaluation in Guangxi Zhuang Autonomous Region in China.