Analysis of driving stability of Kcurve and clothoid on oval curve(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2021年1期
- Page:
- 1-10
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Analysis of driving stability of Kcurve and clothoid on oval curve
- Author(s):
- PAN Bing-hong1; XIE Zhen-jiang1; ZHAO Sheng-lin2; WANG Kai-ming3; WEN Chang-peng1
- (1. School of Highway, Chang’an University, Xi’an 710064, Shaanxi, China; 2. Shaanxi ProvincialTransport Planning Design and Research Institute, Xi’an 710065, Shaanxi, China；3. Ankang Transport Planning and Design Institute, Ankang 725000, Shaanxi, China)
- Keywords:
- road engineering; line design; curve design; Kcurve; simulation model; driving stability
- PACS:
- -
- DOI:
- -
- Abstract:
- To study the feasibility of Kcurve as highway transition curve, the differences of vehicle lateral acceleration, yaw rate, lateral load deviation rate and lateral acceleration change rate between Kcurve and clothoid on oval curve were compared and analyzed, and the driving stability of vehicle running on the Kcurve was studied. According to the mathematical model and setting method of the Kcurve, the pilebystep coordinates of the Kcurve were solved and imported into the dynamic simulation software CarSim, and the simulation model of car running on the Kcurve was established. By changing the radius of curvature at the beginning and the end of the transition curve, the driving state of the passenger car on the oval curve was simulated from the three aspects of the linear change of Kcurve and clothoid, vehicle handling stability and driver comfort. The results show that under the same design index, the bending degree of Kcurve is slightly slower than that of clothoid, and the smaller the radius of circular curve is, the greater the difference between them is. The curvature of the driving track of the vehicle on the Kcurve is a uniform and continuous nonlinear change, which can be used as a transition between two different lines. The smaller the ratio of radius of curvature between the beginning and the end of Kcurve, the larger the value of flat degree parameters k of Kcurve, the closer the change of curvature of Kcurve is to the linear change. The change rate of the lateral acceleration of the vehicle on the Kcurve is smaller in the first half of the curve than that of the clothoid, and larger in the second half of the curve than that of the clothoid. When the design index conforms to the provisions of the route design specification, the change rate of the lateral acceleration meets the requirements of the drivers comfort, and the stability parameters of the vehicle on the Kcurve are always smaller than that of the clothoid, which can meet the requirements of vehicle stability, and the stability is better. It proves that Kcurve can be used as transition curve to design oval curve alignment, widen highway plane design curve type, and increase the diversity and flexibility of line design. 2 tabs, 10 figs, 31 refs.
Last Update: 2021-01-25