潮湿状态下路面抗滑性能分析

Anti-sliding Performance of Pavement under Wet Condition

通过简化圣维南模型计算路面水膜厚度,并根据水力学理论,简化轮胎动水压力,得出潮湿状态下路面附着系数计算公式。应用有限元方法,分析轮胎在车辆荷载作用下下沉量,将其与经验公式对比,验证模型可行性。最后,建立有限元模型模拟轮胎与路面接触,分析在不完全滑水状态下轮胎荷载、行车速度、轮胎气压、水膜厚度对轮胎-路面接触面积及附着系数的影响,分析结果表明,随轮胎荷载增大,轮胎-路面接触面积变大,附着系数增大;随行车速度增大,附着系数在速度40～80km/h区间内下降较为平缓,在速度80km/h后,下降趋势较为急剧;随胎压增大,附着系数在胎压220～260kPa区间内下降较为剧烈,在胎压260kPa以后则变化较小;水膜厚度低时,附着系数随行车速度变化剧烈,而水膜厚度大时,则趋于平缓。

Pavement water film thickness is calculated by simplifying Saint-venant model, then, according to the theo- ry of hydraulics, the hydrodynamic pressure of the tire is simplified, and adhesion coefficient formula of pavement under wet condition is obtained. The subsidence of tire under vehicle load is analyzed by applying the finite element method. Then compare simulating value with experience to validate feasibility of the model. Through simulating interaction be- tween tire and pavement by finite element modeling, the effects of tire load, vehicle speed, tire pressure and water film on adhesion coefficient of pavement under wet condition is analyzed. Analysis result indicates that with the tire load increas- ing, the tire^pavement contact area become larger and the adhesion coefficient increases. Accompanying vehicle speed in creasing, the adhesion coefficient decrease more gently in the interval of 40 km/h to 80 km/h when it decrease more sharply after 80 km/h. With the tire pressure increasing, the adhesion coefficient decrease even more markedly in the in- terval of 220 kPa to 260 kPa when it change little after 260 kPa. The adhesion coefficient change rapidly when water film is thin, and change gently when water film is thick.