基于微胶囊沥青混合料抗剪强度宏-细观研究的自修复沥青道路安定分析

微胶囊沥青混合料是路面新材料的研发热点，但微胶囊掺入会削弱沥青混合料抗车辙性能。现有研究大多针对自愈性能展开，微胶囊沥青道路抗车辙性能优化缺少理论依据。本项目从微胶囊沥青混合料宏观抗剪强度的细观构成机理着手，提出不同粒径微胶囊对抗剪强度的作用机制不同的假说；利用图像处理、剪切流变试验、接触角试验、三轴试验，研究不同温度下微胶囊粒径、掺量对细观性能和宏观抗剪强度参数的影响；通过关联性分析，找出影响各抗剪强度参数的主控细观指标，揭示不同微胶囊对抗剪强度的影响机制，验证假说，并基于细观作用机制建立的抗剪强度模型；进而发展新的沥青路面安定分析方法，开发安定极限求解程序，研究细观性能参数对安定极限的影响规律，并用车辙试验验证；最终形成从材料及结构两方面共同优化微胶囊沥青路面抗车辙性能的设计方法。该项目建立的新理论及新方法有助于推进微胶囊沥青道路在实际工程中的应用，具有重要的科学意义和社会经济价值。

Asphalt mixture containing microcapsules, as one of the advanced functional pavement materials, has attracted more and more attention. The incorporation of microcapsules could adversely affect the rutting resistance of asphalt mixtures. However, most of the existing researches focus on the self-healing performance, therefore the optimization of the rutting resistance performance of microcapsule asphalt pavements lacks relevant basis. This project intends to study the formation mechanism of the macroscopic shear strength from mesoscopic aspects. A hypothesis is proposed that microcapsules with different particle sizes may lead to different mesoscopic mechanisms. Image processing approach, dynamic shear rheological tests, contact angle tests, and triaxial compressive tests will be conducted to study the influence of the microcapsule size and content on the microscopic properties and macroscopic shear strength parameters under different temperatures. Combined with the correlation analysis, the main control mesoscopic indexes that could affect the shear strength parameters will be found out, which will help to reveal the impact mechanism of microcapsules on the shear strength and verify the proposed hypothesis. A shear strength model is therefore proposed based on the mesoscopic mechanism. A new shakedown analysis method based on the microscopic mechanism could also be proposed. The influence of the mesoscopic properties on the shakedown limits can be calculated by developing an optimization solving method. A design method is then proposed to optimize the rutting resistance performance from both material and structure aspects. The new theory and the new design method established in this project could promote the application of microcapsule asphalt mixture in the practice. This project has important scientific significance and socio-economic value.