应用纳米压痕技术表征水化硅酸钙凝胶

Characterization of Calcium Silicate Hydrate Gel Using Nanoindentation Technique

应用纳米压痕技术实测了水化硅酸钙(C-S-H)凝胶的折合模量.结果表明:将特定尺寸的净浆试样进行打磨、抛光和超声波清洗,可制得表面光洁度符合纳米压痕仪要求的试样;不同水化反应阶段生成的C-S-H凝胶的微区力学特征迥异,随着龄期的增长,C-S-H凝胶的折合模量频率分布曲线呈现不同峰值;水化产生的C-S-H凝胶分层包裹在水泥颗粒外围,并以未水化的水泥颗粒为中心向外形成的水化产物其折合模量逐步降低.

The reduced modulus of calcium silicate hydrate（C-S-H） gels was tested by nanoindentation technique,and the preparation technology of samples was developed.It is revealed that after a series of procedures such as solidification,polish gradually and ultrasonic washing,the smooth surface of sample can meet the requirements for nanoindentation.The test results show that several kinds of CS-H gels with distinct micromechanical properties develop during the hydration process.The frequency counts distribution of the reduced modulus of C-S-H gels demonstrates different peaks with increasing ages.The C-S-H gels wrap around the unhydrated cement particles and the reduced modulus decreases progressively outward from the center of cement particles.