Lateral Stability of Tractor-semitrailer on Freeway Horizontal Curve Section

In order to improve the driving safety of tractor-semitrailer on freeway horizontal curve sections, the vehicle dynamics simulation system was established by TruckSim software. Critical wheel lateral adhesion coefficient and lateral load transfer ratio were selected as the lateral stability indicators. The influence of roadway geometrics, speed and gross vehicle mass on lateral stability indicators was investigated by single factor analysis and multi-factor analysis of variance. The models of vehicle lateral stability indicators were calibrated by SPSS software and the driving safety of the tractor-semitrailer on the ice, snow and rainwater covered pavements were evaluated. Results show that the tractor-semitrailer with the gross weight of 48 t skids on the ice pavements. Driving safety of tractor-semitrailer can be ensured at lower speed on snow pavements. On rainwater covered pavements, the tractor-semitrailer can remain a safe speed of 90 km/h. The research results have quantified the influence of roadway geometrics, speeds and gross vehicle weights on the lateral stability of the tractor-semitrailer. The advised vehicle lateral stability models can provide good references for building the freeway driving security system.