基于路表宏观纹理特征的沥青路面全周期抗滑行为研究

In addition to driving behavior, road alignment and vehicle security, traffic safety is related to pavement surface characteristics, which is influenced by both macro-texture and micro-texture. Micro-texture depends on the processing method and physicochemical characteristics of aggregate in mixture; while macro-texture is associated with gradation and construction technology of pavement. Skid-resistance at the regular speed, <60km/h, is decided by micro-texture but when the vehicle speed is more than 60km/h, macro-texture is the dominate factor of pavement skid-resistance. Moreover, macro-texture of the pavement surface changes at different stages of the road life-cycle. To be more specific, the value of macro-texture at design stage is a given virtual number, then turns into a measured maximum value after construction, and after that, it will decay in time during the service life. This project focuses on skid-resistance behavior of asphalt pavement during its whole life-cycle. With the help of the research on asphalt pavement surface texture characteristics, tire mechanical characteristics and fluid flow rules, a framework to evaluate skid-resistance of asphalt pavement is developed. The framework holds the promise for knowing the interactions among tire, fluid and pavement. Furthermore, it also helps to reveal the major factors in skid-resistance performance during the whole life- cycle of pavement. According to the analysis of the coordination of road alignment and texture, requirements for surface macro-texture are proposed for road sections with special alignment and rainfall characteristics. This research system is believed to provide theoretical support at design, construction and service stages of pavement.

车辆行驶安全性除与驾驶行为、道路线形和车辆安全性有关外，还与路面路表特性有关。路面路表特性包括宏观纹理和微观纹理。路面微观纹理特性主要与集料加工方式和集料物理化学特性有关，它决定着车辆常规速度（<60km/h）时的抗滑特性；宏观纹理特性主要与级配类型和施工工艺有关，它决定着车辆高速运动时（>60km/h）的抗滑特性。同时在道路全寿命周期的各阶段，路表宏观纹理也不同，设计阶段为给定的虚拟值；施工完成阶段为实测的最大值；使用阶段则在不断地下降。本项目以沥青路面全周期抗滑特性为研究对象，通过沥青路面表面纹理特征、轮胎力学特性和流体流动规律的研究，建立评价沥青路面抗滑性能的分析方法，揭示轮胎-流体-路面间的相互作用，提出影响路面全生命周期内抗滑性能的主要因素；通过不同道路线形与不同阶段路面宏观纹理的协调分析，提出道路线形与降雨特征和路表宏观纹理的关系，为路面设计、建造、运营各阶段提供理论支撑。

交通安全问题历来是世界各国共同面对的难题，道路交通事故调查分析表明，道路交通雨天事故大多与路面抗滑能力下降有关。对于潮湿路面，由于抗滑性能远小于干燥路面，整车行驶稳定性下降，在遇到紧急制动更易引起水漂而发生交通事故，因此要求道路路面雨天也应提供良好的抗滑性能以保证行车安全。.目前对沥青路面抗滑性能的评价，多是通过摆式摩擦仪或横向力系数测试仪直接测量路面的摩擦系数，这种直接测量的方法易受测试温度、湿度、速度等条件影响，可靠度不高，且不能与车辆实际运行工况挂钩，难以确定安全限值。而路面抗滑性能的评估，不仅涉及橡胶轮胎胎面与路表接触特性，而且与道路表面纹理和轮胎橡胶材料参数紧密相关，需要同时考虑路面宏观纹理和微观纹理、轮胎几何尺寸和花纹分布、两者之间接触以及相对运动状态。.针对雨天沥青路面抗滑行为，本研究建立了基于沥青路面路表纹理信息的雨天路表评价体系。在该评价体系中，考虑了橡胶与分形表面摩擦机理、轮胎路面附着原理、积水路面轮胎水漂机理，并通过数值模拟的手段分析了水漂对于车辆行驶性能的影响。.项目从轮胎橡胶与路面的相互作用出发，研究轮胎与路面之间的摩擦机理；研发了SLP路面纹理测试系统，通过对多条高速公路沥青路面的现场扫描，建立了沥青路面的表面纹理轮廓库，通过运用路表分形摩擦理论，计算得到路面二维功率谱，并推导得出干燥及潮湿条件下橡胶路面动摩擦系数曲线；建立了三维充气花纹轮胎水漂有限元模型，分析了轮胎充气内压、水膜厚度、沥青路面宏观纹理对轮胎滑水的影响；建立CarSim与Matlab/Simlink耦合分析模型，分析不同水膜厚度下动水压力对车辆行驶的影响。预估不同沥青混凝土路面在同一降雨条件下水膜厚度值，得到不同路面在同一降雨条件下车辆行驶稳定性。为之后根据当地气候特点，选择沥青路面面层类型的研究，打下理论基础。