【摘要】 采用扫描电镜技术对不同龄期水泥–水玻璃加固软土的微观结构特征进行观察和研究。借助GIS技术实现了扫描电镜图像的三维可视化,并计算了加固前后土的孔隙率。研究结果表明:水泥–水玻璃的水化产物前期以三硫型水化硫铝酸钙为主,后期以水化硅酸钙为主。水化物形态多为纤维状和棱柱状,通过相互搭接形成网络并包裹土颗粒形成较大颗粒起到加固作用。从化学和物理两个方面分析了水泥–水玻璃固化软土的微观机理。水泥–水玻璃加固软土的微观机理从化学角度主要表现为:水泥的水化水解反应、水玻璃的速凝和增强作用、黏土颗粒与水泥水化物的作用;从物理角度则主要表现为:水化物的充填作用、胶结作用、加筋作用和骨架作用。研究成果对软土地区地基处理和施工有重要意义。更多还原

【Abstract】 The SEM technique is used to observe and study the microstructure of cement-sodium silicate-stabilized soft soils with different curing time. The GIS technique is employed to realize 3D visualization of the image of SEM and to calculate the porosity of the soils before and after stabilization. The results show that the principal components of cement-sodium silicate hydration products are respectively ettringite in early days and hydrated calcium silicate in later days. The shapes of the hydrated products are mainly fibrous and prismatical. They play a role of reinforcement by attaching each other to form network and enwrapping the soil particles to form greater particles. The micromechanism of cement-sodium silicate-stabilized soft soils is analyzed from both chemical and physical points of view. From the chemical point of view it mainly includes hydrolysis and hydration reaction of cement, rapid hardening and reinforcement of sodium silicate and the effect between clay particles and cement, while from the physical point of view, it includes filling effect, cementation effect, reinforcement effect and skeleton effect. It is of important significance for the design and construction of foundation treatment in soft soil areas.更多还原