为减少铰接列车在回头曲线道路上的侧翻事故发生率，提高行车安全性，以国道G215部分路段为例，运用TruckSim软件建立该路段的三维数字模型和六轴铰接列车整车模型，分析了装载质量和质心高度两个因素对车辆在回头曲线道路行驶过程中的侧翻危险可控状态的影响，在侧翻阈值为0.8的条件下得出车辆的回头曲线道路安全可控车速阈值。结果表明：装载质量与回头曲线道路安全可控车速阈值呈指数为负的幂函数关系;质心高度在2.5~2.9m范围内时，安全可控车速阈值受质心高度影响较小，受载重影响大，需重点考虑装载质量来确定安全可控车速;装载质量为30~60t且质心高度为2.5~2.9m时，随着装载质量与质心高度的增加，回头曲线道路安全可控车速阈值减小速率变大，下降率可达46.7%，应综合考虑装载质量与质心高度来确定安全可控车速。

In order to reduce the rollover accident rate of articulated trains driving at switchbacks, and improve the driving safety of vehicles, the software TruckSim was used to establish a 3-D digital model of switchback and a vehicle model of six-axis articulated train, taking part of national highway G215 as an example. The effect of loading mass and centroid height on the rollover risk control state of six-axis articulated train driving at switchback was analyzed. Under the condition that the rollover threshold was 0.8, the vehicle's safe controllable speed threshold of switchback was obtained. The results showed that the loading mass and the safe controllable speed threshold of switchback had a relationship of exponentially negative power function. When the centroid height was within the range of 2.5~2.9m, the safe controllable speed threshold was less affected by the centroid height but more affected by the loading mass, so the loading mass should be considered to determine the safe controllable speed. When the loading mass was 30~60t and the centroid height was 2.5~2.9m, with the increasing of the loading mass and the centroid height, the decrease rate of the safe controllable speed threshold of switchback became bigger, which could reach 46.7%, therefore the loading mass and centroid height should be considered comprehensively to determine the safe controllable speed in this situation.