货车制动毂温度过高是制动失效的主要原因，为提高货车在连续下坡路段行驶的安全性，对平均纵坡设计指标进行细化，研究驾驶人制动行为与货车制动毂温升特性之间的相关性，并基于驾驶人制动行为提出纵坡坡长可靠度设计方法。首先，选取西部山区某高速公路连续下坡路段进行实车试验，采集道路纵坡参数、驾驶人制动行为数据；其次，根据实测数据提出评价指标、位移强度系数和制动毂温度梯度，并基于回归分析探究了位移强度系数和道路平、纵线形的关系以及位移强度系数和制动毂温度梯度的关系；最后，根据驾驶人制动行为和临界温度构建可靠度模型，基于蒙特卡罗仿真法，给出了连续下坡路段不同平均纵坡所对应的临界坡长，并与规范进行对比分析。结果表明：圆曲线半径与位移强度系数相关性不大，纵坡坡度与位移强度系数呈显著正相关，拟合优度r²达0.95；当纵坡坡度大于2%时，驾驶人采取的制动行为多为持续性刹车，与纵坡坡度小于2%时驾驶人多采取点刹的制动行为区别较大，位移强度系数与制动毂温度梯度呈显著正相关，拟合优度r²为0.845；当驾驶人制动比例为85%时，驾驶人制动行为与规范界定坡长的条件基本一致；取可靠度为0.95时，平均纵坡为2.1%~3.0%，连续坡长临界值为14.95~30.12 km。所给出相关参考值考虑了真实行车环境中的随机性，可为平均坡度小于2.5%的坡长设计提供依据。

Excessive temperature of the truck brake hub is a primary factor leading to brake failure. To enhance the safety of trucks traveling on continuous downhill sections, this study refined the average longitudinal slope design parameters and investigated the correlation between driver braking behavior and the temperature rise characte-ristics of truck brake hubs. Based on driver braking behavior, it proposed a reliability design method for longitudinal slope length. Firstly, a continuous downhill section of an expressway in the western mountainous area was selected for real vehicle test, and the road longitudinal slope parameters and driver braking behavior data were collected. Secondly, according to the measured data, the evaluation indexes were proposed: displacement intensity coefficient and brake hub temperature gradient. This study investigated the relationship between displacement intensity coefficient and road profile, both longitudinal and transverse, as well as the relationship between displacement intensity coefficient and brake hub temperature gradient through regression analysis. Finally, a reliability model was constructed based on the driver’s braking behavior and critical temperature. Using the Monte Carlo simulation, critical slope lengths corresponding to different average longitudinal slopes on continuous downhill sections were determined and compared with the specification. The results indicated that there is a weak correlation between the radius of the circular curve and the displacement intensity coefficient, while there is a significant positively correlation between the longitudinal slope gradient and the displacement intensity coefficient, and the goodness of fit r² is 0.95. When the longitudinal slope gradient is greater than 2%, the braking measures taken by drivers are mostly sustained braking, which is more different from the braking behavior of drivers mostly taking point braking when the longitudinal slope gradient is less than 2%. The displacement intensity coefficient and the temperature gradient of the braking hub are significantly positively correlated with the goodness-of-fit r² is 0.845. When the proportion of the driver braking for 85%, the braking behavior of the driver at this time with the specification of defining the conditions of the slope length is basically the same. When the reliability is 0.95, the average longitudinal slope is 2.1%~3.0%, and the critical value of the continuous slope length is 14.95~30.12 km. The given reference values take into account the randomness in the real driving environment, and provide a basis for the design of the slope length with an average slope of less than 2.5%.