In order to provide a reference for gradation design of asphalt mixture anti-slip surface, the contact stress distribution characteristics of tire/road under different kneading time were studied based on high precision pressure film technology.By comparing two kinds of coarse aggregate and two types of asphalt mixture, the attenua-tion law of asphalt pavement skid resistance performance under the action of wheel-load was studied.And the eval-uation index of asphalt pavement skid resistance performance was established from contact mechanics standpoint. The results showed that the contact stress between tire and road is a kind of significant non-uniform distribution, in-cluding the effective contact area and stress concentration effect.In the initial state, the effective contact area and stress concentration of the tire/road are mainly related to the gradation design.However, the effective contact area continues to increase and the stress concentration decreases with the second compaction and coarse aggregate abra-sion of pavement surface in the kneading process.Stress concentration distribution index can well describe the stress concentration effect, and the analysis showed that there is a good linear relationship between tire contact stress concentration and road friction coefficient.Experiments showed that the skeleton dense gradation and high-quality coarse aggregate are conducive to improve the durability of asphalt pavement skid-resistant performance. Due to the effect of mineral aggregate gradation is more significant, it should be emphasized in the design of wearing surface.%为了给抗滑表层沥青混合料级配设计提供参考,基于高精度压力胶片测试技术,开展不同搓揉时间下的胎/路接触应力分布特性研究.通过2种粗集料2种类型沥青混合料的对比,研究轮胎作用下沥青路面的抗滑性能衰减规律;并从接触力学的角度建立沥青路面抗滑性能评价指标.结果表明:轮胎与路面接触应力呈现显著的非均匀分布,主要包括有效接触面积与应力集中效应.初始状态下胎/路有效接触面积与应力集中主要与级配设计有关;而在搓揉过程中,随着路面构造的二次圧密与粗集料磨耗,有效接触面积持续增加,应力集中减少;应力集中分布度指标可以较好描述应力集中效应.分析表明,轮胎接触应力集中与路面摩擦系数呈现良好的线性关系.试验证明,骨架密实型级配与优质粗集料均有利于提高沥青路面抗滑耐久性能;而级配的影响更显著,磨耗层设计中应当给以重视.
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