山区圆曲线路段半挂汽车列车行驶安全性分析

根据山区圆曲线路段的特点, 分析了轮胎的受力和变形情况, 建立了半挂汽车列车与山区圆曲线路段的耦合动力学模型。以牵引车和半挂车的轮胎侧偏角和折叠角为指标, 运用提出的动力学仿真法分析了不同车速下圆曲线路段半径、超高、滑动附着系数对半挂汽车列车行驶安全性的影响, 并与运行速度法和理论极限速度法的计算结果进行对比。仿真结果表明: 当圆曲线半径为125m, 路面超高为2%, 滑动附着系数分别为0.20、0.35、0.50、0.80时, 运用动力学仿真法求得的临界安全车速分别为20、35、55、72km·h^-1, 运用运行速度法求得的临界安全车速均为50km·h^-1, 运用理论极限速度法求得的临界安全车速分别为18、20、25、30km·h^-1; 当圆曲线半径为250m, 滑动附着系数为0.35, 超高分别为0、2%、4%、6%时, 运用动力学仿真法求得的临界安全车速分别为35、38、25、20km·h^-1, 运用运行速度法求得的临界安全车速均为60km·h^-1, 运用理论极限速度法求得的临界安全车速分别为30、31、32、33km·h^-1; 当路面超高为6%, 滑动附着系数为0.50, 圆曲线半径分别为125、250、400、650m时, 运用动力学仿真法求得的临界安全车速分别为58、62、70、72km·h^-1, 运用运行速度法求得的临界安全车速分别为50、60、68、71km·h^-1, 运用理论极限速度法求得的临界安全车速分别为28、37、48、60km·h^-1。可见, 提出的动力学仿真法考虑了车辆悬架动力学特性、天气与路面条件, 可以准确描述半挂汽车列车的运行状态。

Driving safety analysis of semi-trailer train at circular curve section in mountain area

According to the characteristics of circular curve section for mountain area, the stress and deformation conditions of tire were analyzed, and the dynamics coupling model of semi-trailer train and the circular curve section in mountain area was established. The tire slip angles and articulation angle of tractor and semi-trailer were taken as indexes, the influences of the radius, superelevation and sliding adhesion coefficient of circular curve section on the driving safety of semi-trailer train under various speeds were analyzed by using the proposed dynamics simulation method, and the calculation results among running speed method, theoretic limit speed method and dynamics simulation method were compared. Simulation result shows that when the circular curve radius is 125 m, the superelevation is 2 %, the sliding adhesion coefficients are 0. 20, 0. 35, 0. 50 and 0.80 respectively, the critical safe speeds are 20, 35, 55, 72 km · h-1 by using dynamics simulation method, all the critical safe speeds are 50 km · h-1 by using running speed method, and the critical safe speeds are 20, 35, 55, 72 km· h-1 by using theoretic limit speed method respectively. When the circular curve radius is 250 m, the sliding adhesion coefficient is 0. 35, the superelevation are O, 2%, 40/40 and 6% respectively, the critical safe speeds are 35, 38, 25, 20 km · h-1 by using dynamics simulation method respectively, all the critical safe speeds are 60 km · h-1 by using running speed method, and the critical safe speeds are 30, 31, 32, 33 km · h-1 by using theoretic limit speed method respectively. When the superelevation is 6%, the sliding adhesion coefficient is O. 50, the circular curve radii are 125, 250, 400, 650 m respectively, the critical safe speeds are 58, 62, 70, 72 km ~ h-~ by using dynamics simulation method respectively, the critical safe speeds are 50, 60, 68, 71 km ·h-1 by using running speed method respectively, and the critical safe speeds are 28, 37, 48, 60 km · h-1 by using theoretic limit speed method respectively. In the proposed dynamics simulation method, the vehicle suspension dynamics characteristic, weather and road conditions are considered, and the running state of semi-trailer train can be described accurately.