Design index of transition section of ramp lane number change(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2018年01期
- Page:
- 82-88
- Research Field:
- 交通工程
- Publishing date:
Info
- Title:
- Design index of transition section of ramp lane number change
- Author(s):
- PAN Bing-hong; LIU Bin; ZHOU Hai-yu; HUO Yong-fu; WU Sheng-quan
- 1. School of Highway, Chang’an University, Xi’an 710064, Shaanxi, China； 2. Key Laboratory for Special Area Highway Engineering of Ministry of Education, Xi’an 710064, Shaanxi, China
- Keywords:
- traffic engineering; index section of transition; lane changing model; transition section; simulation model
- PACS:
- U491.22
- DOI:
- -
- Abstract:
- In order to study the length and gradual change rate of transition section of ramp lane number change, the driving characteristics of transition section of ramp lane number change were analyzed, and a way to study these two design indexes by using lane changing model was put forward according to the previous research results. Firstly, the lane changing model of constant velocity offset cosine curve satisfying the vehicle running characteristic in transition section was established, and the rationality of the model was proved by using the measured data of UMRR traffic management sensor in Germany. Then two key parameters of the maximum lateral acceleration and the maximum lateral acceleration change rate of the model were studied in depth. Finally, based on this model, the recommended values of design indexes for length and gradual change rate of transition section of ramp lane number change based on design speed were proposed, and simulation models of cars and large trucks were built by using CarSin and TrcukSim vehicle dynamics simulation software, respectively. The proposed values were compared with the recommended values of guidelines for design of highway grade-separated intersections (JTG/T D21—2014) by using this model. The results show that the proposed design index of transition section of ramp lane number change based on the established constant velocity offset cosine curve model can ensure the vehicle to travel safely and comfortably along the specific optimal trajectory in transition section. The standard recommended values can only meet the lane changing behavior of 40 km/h design speed of the vehicle, at this time, the maximum lateral force coefficient of the truck is 0.142. When the design speed is below 40 km/h, the lateral force coefficient is far below the allowable value, resulting in the waste of length of transition section. When the design speed is greater than 40 km/h, the lateral force coefficient of vehicle exceeds the limit. When the speed reaches 80 km/h, the lateral force coefficient exceeds the limit by 315%, the vehicle is not safe in this state. In view of this, it can be speculated that the standard recommended values can only satisfy the design speed of 40 km/h vehicle. When the speed is above and below 40 km/h, the index of transition section of ramp lane number change is not reasonable.
Last Update: 2018-02-06