Safety evaluation of urban expressway traffic flow operation status(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年2期
- Page:
- 90-98
- Research Field:
- 交通工程
- Publishing date:
Info
- Title:
- Safety evaluation of urban expressway traffic flow operation status
- Author(s):
- DAI Xuezhen1; YUAN Renteng1; ZHOU Yanan1; WU Zhiwei2
- （1. School of Highway, Changan University, Xian 710064, Shaanxi, China;2. Henan Dingzhi Engineering Consulting Co., Ltd., Zhengzhou 450000, Henan, China）
- Keywords:
- traffic engineering; traffic safety; urban expressway; DEA; effective frontier
- PACS:
- -
- DOI:
- -
- Abstract:
- To evaluate the traffic safety of driving on urban expressway, a method based on data envelopment analysis (DEA) was proposed to evaluate the safety of traffic flow. In addition, the practicability of the evaluation method was verified. Some indexes which can reflect the stability of traffic flow were analyzed deeply. The traffic stability indexes were divided into the fundamental indexes and the characteristic indexes. The fundamental indexes represented by traffic flow, velocity and density, were selected as the input indexes. The coefficients of speed standard deviation, the rate of lane changing and the average of the headway, were selected as the output indexes. Then the nonexpected indexes were converted to the expected indexes by using linear transformation. The undesired output indexes were converted to the desire output indexes according to linear transformation. Based on EDA method, the model of the traffic safety evaluation on urban expressway was established. The difference of input and output indexes in every evaluation segment were calculated, so the relative safety of multiple evaluation samples could be obtained through the model. Take 10 segments of the Xian Ring Expressway including 4 weaving segments as example. The radar speed gun and video methods were used to collect traffic data. The LINGO11.0 software was used to solve this model. The results show that there are 6 segments, which are effective units and the road safety degree is relatively effective, while 4 segments are ineffective units with potential safety hazards. The relative safety degree of road sections A, B, C and J of the ineffective units are 97%, 88%, 98% and 96% respectively. Based on the analysis of the evaluation results, it is proposed that when the input indexes such as traffic flow, velocity or traffic density change such as increasing, the hidden danger of road traffic safety is likely to be magnified and traffic accidents are likely to occur. 3 tabs, 3 figs, 33 refs.
Last Update: 2020-04-09