【摘要】 利用同步辐射X射线小角散射技术表征超低水灰比水泥水化早期产物分形结构,研究水化水泥早龄期微结构及演变。水泥水化早期水化产物双分形结构表明:水泥水化硅酸钙纳米凝胶颗粒随机堆积,内外层水化产物中纳米凝胶粒子结构分别具备不同的自相似性;内层水化产物中高密度凝胶堆积紧密,早龄期时随水化时间增加,堆积密度降低。外层水化产物中低密度凝胶堆积较为松弛,早龄期时随水化时间增加,堆积密度也在降低;水化诱导期生成结构最为致密的一层凝胶产物,诱导期后,凝胶产物层堆积密度随水化龄期的增加而减小,水化反应平缓后,凝胶堆积密度的演变也趋于平缓。更多还原

【Abstract】 Synchrotron small angle X-ray scattering(SAXS) was applied for non-destructive measure of fractal structure of hydrating cement.Early age microstructure of the cement with ultra low water to cement ratio was investigated.Fractal structure of the hydra-tion products indicates that nano C-S-H particles are packed randomly.Double fractal results from two types of structural self-similarity locating in the inner and outer hydration products respectively.Packing of the high density C-S-H within the inner hydra-tion productions is dense,and packing density degrease with hydration,while packing of the low density C-S-H within the outer hydra-tion productions is looser,and packing density also degrease with hydration.The densest packing of a layer of nano C-S-H particles is produced at the induction period of cement hydration.At acceleration period,packing density of the layer degreases with hydration of cement.However,evolution of packing density of the layer becomes flat after acceleration period of cement hydration.更多还原