适应6轴铰接列车动力性的高速公路最大纵坡坡度和坡长
Maximum grade and length of longitudinal slope adapted to dynamic performance of six-axis articulated vehicle

针对当今中国高速公路货运主导车型6轴铰接列车以满载状态在相同纵坡条件下行驶时,其性能差于《公路工程技术标准》(JTG B01―2014)中纵坡设计代表车型的问题,采用典型平路试验和实际道路试验相结合的方法,获得了该主导车型的发动机使用外特性曲线,分析了试验车发动机转矩、功率与发动机转速的关系; 依据汽车行驶受力方程,建立了该主导车型在各个挡位下的坡度与车速的关系曲线,确定了不同纵坡坡度时,发动机全负荷状态下车辆稳定行驶的最大平衡速度,获得了该主导车型的加速性能曲线和减速性能曲线,提出了符合中国当前货运车型变化的高速公路上坡方向纵坡坡度、坡长等主要控制指标。研究结果表明:相比于《公路工程技术标准》(JTG B01―2014),在相同纵坡条件下,由于主导车型比功率的降低,其平衡速度较标准中纵坡设计代表车型对应的平衡速度降低了20%～30%,且适应其动力性的最大纵坡坡度比标准中规定的纵坡坡度小50%,因此,中国当前主导货运车辆动力性能不适应高速公路纵坡条件; 根据6轴铰接列车在不同纵坡上的加减速特性,满足6轴铰接列车爬坡需求的最大纵坡坡长随坡度的增大而降低,且降低幅度逐渐增大,最大降幅达到60%。
For the problem that under the same longitudinal grade, the dynamic performance of a representative(six-axis articulated)vehicle in highway freight transportation in China with full load was worse than the representative vehicle for the longitudinal slope design in Technical Standard of Highway Engineering(JTG B01―2014), the actual engine performance curves of this representative type of vehicle were obtained by combining the typical flat road test and the actual road test. The relationship between engine torque and engine rotate speed, as well as the relationship between engine power and engine rotate speed were analyzed. The relationship curves of slope grade-vehicle speed were established under different gears according to the motor vehicle motion equation. The maximum equilibrium vehicle speed under the condition of steady running, full engine load and different longitudinal grades were determined. The curves of acceleration and deceleration performance of this representative type of vehicle were gained to propose the primary longitudinal slope design indicators such as the grade and length of the longitudinal slope, which conform to the change of freight vehicle type in China. Research result shows that under the same longitudinal grade, owing to the reduction in the specific power of the representative vehicle, its equilibrium speed decreases by 20%-30% compared to the representative vehicle for the longitudinal slope design in Technical Standard of Highway Engineering(JTG B01―2014). The maximum longitudinal grade adapted to the six-axis articulated vehicle is 50% lower than that specified in the standard. Therefore, the dynamic performance of the current representative vehicle cannot adapt to highway longitudinal slope design indicators. According to the acceleration and deceleration characteristics of the six-axis articulated vehicle under different longitudinal grades, the maximum slope length satisfied the climbing demand of six-axis articulated vehicle decreases with the increase of longitudinal grade, the reduction increases gradually,