宏观形貌对沥青路面黏性滑水的影响分析

The Influence of Macro-texture on Viscous Hydroplaning of Wet Asphalt Pavement

为研究宏观构造对潮湿沥青路面抗滑性能的影响,引入宏观形貌概率正态分布模型,构建潮湿路面-车轮相互作用下的动水压力解析方程及数值解算方法;并将分布模型与现行的路面抗滑指标MTD相联系。在此基础上,以黏性动水压力为基本指标,分析潮湿工况下,AC-13、SMA-13及OGFC-13这3类路型的路面抗滑性能。计算表明,潮湿路面薄层水膜条件下的黏性滑水不完全等同于积水路面条件下的惯性滑水,其胎下动水压分布沿行驶方向显现出非线性变化的特征,且在胎面临近完全接触区边界附近达到峰值后迅速衰减;同时,黏性滑水产生的承载力随行驶速度呈线性增长。另一方面,黏性滑水产生的动水压力与水膜厚度和路面构造深度的比值相关:当路面水膜厚度h在0~3σ之间,动水压力明显随水膜增厚而减小、随构造深度的增加而减小;当路面水膜厚度大于3σ或构造深度足够大时,水膜厚度和构造深度的影响将随之减弱。

In order to study the influence of macro-textureonthe skid resistance of wet asphalt pavement,the normal probability distribution model of macro-texture was introduced to construct the analytic equation and numerical method of hydrodynamic pressure under the interaction of wet pavement and rolling tires.The probability distribution model was associated with the mean texture depth which is the design index of skid-resistance in the current specification.Based on the above,the skid resistance performance of AC-13,SMA-13 and OGFC-13 were analyzed in wet condition,with the hydrodynamic pressure as the key indicator.The results show that the hydroplaning caused by viscous reason on thin water film is not completely equivalent to that caused byinertial reason.The hydrodynamic pressure distribution has a characteristic of nonlinear change at the longitudinal direction,and the maximum value of hydrodynamic pressure is closed to the back of contact zone and then decays rapidly.The bearing force under viscous hydroplaning condition has a relationship of linear growth with the speed.On the other side,the hydrodynamic pressure produced by viscous hydroplaning exists relations with the ratio of water film thickness to pavement texture depth:the hydrodynamic pressure decreases with the increment of film thickness and texture depth,when the thickness of water film is between 0 and 3σ;the influence of film thickness and texture depth will be weakened when the film thicknessis great than 3σor the texture depth is large enough.