导　　师： 胡曙光

学科专业： 081406

授予学位： 博士

作　　者： ;

机构地区： 武汉理工大学

摘　　要： 高速铁路是我国交通建设发展的重要方向。无碴轨道具有结构整体性与稳定性好以及修量少的优点,是铁路高速化的发展方向。板式轨道是一种先进的无碴轨道结构形式,它由混凝土道床、CA砂浆层、轨道板等部分组成,其中CA砂浆是用于轨道板与混凝土道床之间的结构层,主要起支承轨道板、缓冲高速列车荷载的作用。CA砂浆/(cement asphalt mortar,简称CA砂浆/)是由水泥、沥青乳液等多种材料组成的一种有机无机复合材料。作为全面支承轨道板的垫层结构,要求其具有足够的强度和必要的弹性,其性能好坏直接影响到板式轨道结构的耐久性、安全性与经济性。随着我国高速铁路网建设规划的全面实施,无碴轨道技术已成为当前急需重点研究与快速开发的关键技术。 本文通过对CA材料物理力学性能、耐久性和耐候性能的系统试验、足尺工程试验以及CA材料设计制备理论研究,揭示了CA材料的组成、结构与性能之间的相互影响和变化规律,为促进该类材料的发展应用提供了重要的参考。 本文进行的主要工作和取得的重要成果有: 研究并揭示了水泥水化硬化与沥青乳液破乳胶结相互作用的机理,阐释了CA砂浆胶结硬化与结构形成全过程,将其分为悬浮分散、水泥水化与沥青乳液破乳胶结、沥青连续网络结构形成、硬化体结构发展四个阶段,建立了以沥青为连续相、水泥等无机材料为分散相的CA砂浆空间网络结构模型,为设计、制备CA砂浆提供了理论依据。 依据CA砂浆的理想结构模型,结合砂浆硬化体结构的组成,提出了计算CA砂浆中无机材料表层沥青膜厚的理论公式,并建立了沥青膜厚度和材料性能的相关性,提出了制备CA砂浆的最佳沥青用量控制与修正方法,对高性能CA砂浆材料的制备具有指导意义。 针对CA砂浆材料组成复杂、各组成之间性能影响较� High speed railway is an important pillar in the transportation development of China. Ballastless track has manifold advantages of excellent structural integrity and stability, lower maintenance requirements, bearing the potential for railway to high speed. Slab track is an advanced structure form, consisting of concrete roadbed, elastic cushion, track slab, etc. The elastic cushion, cement asphalt mortar /(more often known as CA mortar/) is sandwiched between two slabs and serves the purpose of supporting slab track and cushion the impact of wheel rail. CA mortar is composed of cement, asphalt emulsion, fine aggregate and a variety of admixtures and is a high performance composite material. It has the combined merits of high strength and good elasticity, and is crucial to the durability, safety and economy of slab track. With the implementation of the construction and design of China's high speed railway network, ballastless track has become the key technology deserving keen attention and rapid development. The paper undertook a systematic study on the physical and mechanical properties, durability and weatherability, in-situ construction technology and the design and preparation of CA mortar, and clarified the relationship between composition, structure and performance, providing essential basis for the development and application of CA mortar. The paper was organized into five section and main results were briefly given as follows: The first section revealed the mutual interaction between cement hydration and asphalt emulsion breaking and proposed a hypothesized evolution in the hardening of CA mortar, which was divided into four stages: suspension and dispersion, cement hydration and asphalt emulsion breaking, formation of a continuous asphalt network and development of hardened matrix. An ideal model of CA mortar was established in which asphalt was the continuous phase, cement and other inorganic components acted as the dispersed phase and underpinned the theoretical foundation for the design an

关 键 词： 砂浆 沥青乳液 水泥 板式无碴轨道 高速铁路

领　　域： [交通运输工程]