水泥混凝土的孔径连续分布及过渡区特征与其渗透行为关系研究

It is universally acknowledged that the durability of concrete is responsible for the aggregation and migration of the ion causing corrosion. In initial deterioration period, the permeability of concrete matrix is the key factor to attacking and migration of fluid including liquid and gas, which determined the durability of concrete. In classical percolation theory, the intrinsic permeability of materials is only concerned with the pore properties of materials. In this project, the characteristic of pore size distribution in concrete is researched by the mathematical method of particle size distribution analysis, a mathematical model to describe the continuous pore size distribution in concrete is proposed. The transition zone parameters of concrete are studies on measurement. The quantitative relationship between parameters of the mathematical model, the transition zone, the composition of concrete, hydration degree of cement pastes and curing condition is analyzed, and the migration channels and the conditions to impede the attacking and migration of ion in concrete are researched. A new method to describe the migration characteristic of ion causing corrosion in concrete qualitatively and quantitatively is developed in this project. This has practical significance to preparation of high impermeability concrete.

一般情况下，混凝土的耐久性均与腐蚀性离子在混凝土内迁移有关。在破坏早期，混凝土的耐久性能均与特定的流体在混凝土内部迁移的难易程度有关，这取决于混凝土本体的渗透性，经典的渗流理论认为材料的本征渗透性能只与材料的孔性质有关。本课题借鉴颗粒尺寸分布的概念及其相关的数学工具来研究水泥混凝土中的孔径分布的特点，提出合理的、用于描述混凝土中从大孔到微孔的孔径连续分布数学模型，建立定量描述混凝土界面过渡区特征参数，在此基础上研究混凝土孔径连续分布模型参数和描述过渡区特征参数与混凝土组成、水化进程和养护条件的定量关系，同时还探索腐蚀性离子进入水泥混凝土的迁移通道和阻碍条件，创新性地寻求定性和定量表征腐蚀性离子在水泥混凝土中的迁移特性，进一步了解混凝土的渗透性能，对高抗渗性混凝土的制备具有明显的指导意义。

一般情况下，混凝土的耐久性均与腐蚀性离子在混凝土内迁移有关。在破坏早期，混凝土的耐久性能均与特定的流体在混凝土内部迁移的难易程度有关，这取决于混凝土本体的渗透性，经典的渗流理论认为材料的本征渗透性能只与材料的孔性质有关。本项目分析水泥混凝土中的孔径分布的特点，提出了合理的、用于描述混凝土中从大孔到微孔的孔径连续分布数学模型，建立了定量描述混凝土界面过渡区特征参数，在此基础上研究了混凝土孔径连续分布模型参数和描述过渡区特征参数与混凝土组成、水化进程和养护条件的定量关系，同时还探索了腐蚀性离子进入水泥混凝土的迁移通道和阻碍条件，创新性地定量表征了腐蚀性离子在水泥混凝土中的迁移特性。研究成果对进一步揭示混凝土的渗透规律、制备高抗渗性混凝土具有较好的学术意义。