公路下坡段缓坡设计指标研究

Study on Design Index of Gentle Slope in Downhill Section of Highway

为减小货车行车速度,降低制动频率,确保连续下坡路段的行车安全,需在高速公路下坡路段设置缓坡。从现有规范看,其关于连续下坡段缓坡指标的设计较粗略。基于此,论文基于货运车辆的具体情况,以DFL4251A15六轴铰接列车为依托,分析连续下坡路段货车的受力状态,探讨制动条件下货车在下坡路段保持匀速行驶时的坡度值,并以此为缓坡临界纵坡提出各制动挡位下,各行车速度对应的缓坡坡度值。

In order to reduce the truck running speed,reduce the braking frequency,increase the safety of continuous downhill sections,it is necessary to set a gentle slope in the downhill section ofthe expressway.From the existing specifications,the design ofthe gentle slope index of the continuous downhill section is rough.Based on this,based on the specific situation of freight vehicles and DFL4251A15 six-axis articulated train,this paper analyzes the stress state ofthe truck in the continuous downhill section,and discusses the slope value ofthe truck when it keeps a constant speed in the downhill section under braking conditions.Taking this as the critical longitudinal slope of gentle slope,the gentle slope slopevalue corresponding to each running speedunder eachbrakinggear is proposed.