Vehicle skidding risk evaluation based on the lateral inhomogeneous distribution of pavement friction coefficients

Abstract

Current methods for assessing pavement skid resistance are based on spot or line sampling, neglecting the lateral skidding risk of vehicles derived from the uneven distribution of pavement friction coefficients. Through mechanical analysis, this study illustrates that vehicles are susceptible to lateral instability when the road surface exhibits unequal friction coefficients between the left and right wheel tracks. Based on this finding, vehicle dynamics simulations are conducted to evaluate longitudinal and lateral braking distances under varying speeds and friction coefficient distributions. It was found that when the friction coefficients are below 0.5, the risk is dominated by the longitudinal braking distance. Conversely, when there is a significant disparity in friction coefficients between the left and right wheel tracks (exceeding 0.2), the risk is predominantly associated with lateral skidding. Sensitivity analysis further examined the combined effects of friction disparities and driving speed, revealing that when speed exceeds 80 km/h, lateral skidding risk induced by uneven friction becomes the dominant factor over longitudinal braking risk. A skidding risk assessment method is then proposed, incorporating simulation results and braking distance thresholds. Furthermore, a comprehensive evaluation framework is established, encompassing sampling strategies, paired friction coefficient analysis for left and right wheel tracks, and risk quantification. The key contribution of this study lies in highlighting the critical yet often neglected impact of lateral friction coefficient variation on vehicle skid safety. By simulating its risk implications, this research proposes a novel overall evaluation framework for pavement skid resistance, leveraging field-collected data. The proposed approach expands the scope of traditional skid resistance assessment, offering a more holistic perspective for improving road safety.