湿热环境沥青路面抗滑性能衰减机理与模型研究

Fair anti-slide performance of pavement is the premise to ensure a safe and fast traffic, is the most basic requirement for a road. Recent studies and pavement tests indicate that the anti-slide performance's attenuation of asphalt pavement is mainly due to the compaction and migration of asphalt mixtures in hot and humid environment. Accordingly, in this project the high-precision industrial CT will be applied to obtain the macrostructures and mesostructures of asphalt pavement's anti-slide surface, which is combined with the results of material tests to analyze the asphalt mastic and aggregates' volumetric components and the material properties, and to obtain the asphalt mastic and aggregates' migration law by real-time scanning. The 2D and 3D numerical model will be found based on CT images, then finite element method and discrete element method are applied to simulate the stress and deformation of anti-slide surface, the model and boundary conditions are calibrated via anti-slide surface tests. The material test device developed by the research group called "Driving Wheel Pavement Material Analyzer" is adopted to carry on the indoor accelerate tests for anti-slide surface material under multi-factors. Based on the CT scanning and numerical simulation results, the anti-slide performance's decay model of asphalt pavement will be established and prevention measures will be put forward. This project can improve the asphalt mixtures' functional design theory and procedure, and provide a theoretical basis and support for the design and research of asphalt pavement's anti-slide surface.

良好的路面抗滑性能是保证车辆安全、快速行驶的前提，是对路面的最基本要求。已有的研究和实际路面检测显示，沥青路面早期抗滑性能的衰减主要是由于湿热重载交通环境下沥青混合料的压密与迁移。据此，本项目拟采用高精度工业CT扫描获得沥青路面抗滑表层宏观与细观结构，结合材料试验分析抗滑表层中沥青胶浆和集料的体积组成和材料特性，通过CT实时扫描获取荷载作用下沥青胶浆和集料的迁移规律；并基于CT数字图像建立二维及三维数值模型，采用有限单元法及离散单元法模拟抗滑表层中各体积组成的力学特性和变形规律，通过抗滑表层力学试验校核数值模型的边界条件和参数；进一步利用课题组已研制的主驱动轮式路面材料测试装置，对抗滑表层材料进行多因素室内加速加载试验研究，结合CT扫描和数值模拟结果，建立路面抗滑性能衰减模型，提出防治措施。本项目能够完善功能型沥青混合料设计理论与方法，并为沥青路面抗滑表层的设计和研究提供理论依据和支持。

为研究车辆荷载作用下沥青混合料内部结构变化对路面抗滑性能衰减的影响，本研究基于工业CT技术和数字图像处理技术对沥青混合料内部组分结构进行研究，结果表明空隙和沥青砂浆随着荷载作用发生的迁移和变化; 采用离散元模拟分析得出粗集料之间接触的变化和应力传递规律。提出表面纹理指数评价路面抗滑性能，基于加速加载试验并采用国际摩阻数IFI指标建立沥青路面随路面抗滑性能衰减模型，为沥青路面抗滑表层沥青混合料设计提供了理论依据和支持。最后，提出行车轨迹横向干预标线技术和渗固封层技术作为抗滑性能衰减的控制与改善措施。