水泥乳化沥青砂浆流变性能、破乳行为及其对硬化体性能的影响研究

The poor rheological properties and demulsifying behavior of cement asphalt emulsion (CA) mortar have a strong effect on its workability and the properties of hardened CA mortar in ballastless track. The rheological properties and demulsifying behavior of cement asphalt emulsion (CA) mortar, and their effect on the workability of fresh CA mortar and the properties of hardened CA mortar will be investigated in this project. In the basis of the rheological properties of CA mortar, numerical simulation and the fluidity test of CA mortar will be investigated and the sedimentation theory of fine particles in thixotropic paste will be studied, and then the relation between rheology and workability about CA mortar will be established. The demulsifying behavior of asphalt emulsion in CA mortar in and after the mixing will be quantificationally studied according to the rheology. Factors influencing the demulsifying behavior as well as the corresponding mechanism will be studied, and the control method on the demulsifying behavior of asphalt emulsion will be proposed. In the basis of the study of the demulsifying behavior, the effect of different demulsifying rate on the cement hydration, microstructure, mechanical properties, and durability of CA mortar will be studied.. In the basis of the rheological properties and demulsifying behavior of CA mortar through the above study, the relation between the rheological properties and workability of CA mortar, the relation between the rheological properties and demulsifying behavior, and the relation of the demulsifying behavior with microstructure, mechanical properties, and durability will be established. As a result, the integration of design and control on the workability, mechanical properties, and durability of CA mortar will be realized.

不良的流变性能和破乳行为严重影响无砟轨道用水泥乳化沥青砂浆（cement asphalt emulsion mortar，简称CA砂浆）的施工性能及硬化体性能。本项目针对CA砂浆的流变性能、破乳行为及其对CA砂浆施工性能和硬化体性能的影响开展研究。以流变性能为基础，研究CA砂浆流动性试验与数值模拟，建立触变性浆体中细颗粒沉降理论，以此建立流变性能与施工性能的关系；基于流变性能定量研究CA砂浆中乳化沥青在拌和过程及拌和后的破乳行为，分析破乳行为的影响因素和机理，提出乳化沥青破乳行为的控制方法；并在此基础上，研究不同破乳行为对水泥水化、CA砂浆的微观结构、力学性能及耐久性的影响。.通过以上研究，以CA砂浆流变性能和破乳行为为基础，建立CA砂浆流变性能与施工性能、流变性能与破乳行为的关系，破乳行为与微观结构、力学性能和耐久性的关系，从而实现CA砂浆施工性能、力学性能及耐久性的一体化设计与控制。

水泥乳化沥青（CA）砂浆是高速铁路无砟轨道的关键材料，水泥乳化沥青胶浆的流变性能和乳化沥青的破乳行为对CA砂浆的工作性能和力学性能具有重要影响，为此本项目研究了CA胶浆的流变性能和乳化沥青的破乳行为及其对硬化体性能的影响研究，具体开展和取得的成果如下：第一、完成水泥乳化沥青胶浆流变性能的基本规律及影响因素分析，提出了不同组成的CA胶浆黏度预测模型、触变性评价模型，并系统分析了CA胶浆的屈服应力、黏度及触变性的影响因素；第二、基于流变性能的水泥乳化沥青胶浆破乳行为分析，揭示了乳化沥青在水泥水化离子作用和水泥颗粒作用下的两种破乳行为，为调控乳化沥青在水泥影响下的破乳作用提供了理论依据；第三、进行了水泥乳化沥青砂浆力学性能预测研究与微观结构，建立了不同沥青与水泥体积比及不同温度下的CA砂浆抗压强度和弹性模量的预测模型，为CA砂浆的力学性能及感温性研究提供了理论参考；第四、基于CA胶浆流变性能和破乳行为为基础，研究了水泥乳化沥青混合料力学性能机理，并提出了力学性能的提升方法研究。. 本项目研究揭示了CA胶浆流变性能的基本规律及影响机制，揭示了乳化沥青在水泥作用下的破乳行为及影响因素，完成了CA砂浆的力学性能预测研究，并提出了基于CA胶浆流变性能及破乳行为的水泥乳化沥青混合料力学性能提升方法。以上工作和得到科学规律可为CA复合材料的设计、基本性能规律研究以及力学性能提升提供理论基础。