摘要
通过对水泥净浆水化放热量、Ca(OH)2的含量和化学结合水量及水泥砂浆的孔结构的测定,研究减缩剂对水泥基材料水化和孔结构的影响。结果表明:减缩剂会延缓水泥的水化,且随着龄期的发展,延缓作用渐弱。具体表现为减缩剂会降低水泥水化放热的峰值,延迟峰值出现的时间,减小水化放热量;减缩剂能够减小水泥净浆的化学结合水量;龄期为3d时,掺减缩剂的净浆中Ca(OH)2的含量明显低于空白样的,28d时与空白样的相当;减缩剂能够减小水泥砂浆中多害孔和有害孔的孔体积,增加无害孔的孔体积。另外还对减缩剂在水泥基材料中存在的形态提出设想。
The effect of shrinkage reducing admixture （SRA） on hydration process and pore structure of cement-based materials was studied. The hydration heat, chemically combined water and Ca（OH）2 content of cement paste and pore structure of mortar were measured by isothermal calorimeter, gravimetric method, X-ray diffraction and mercury intrusion porosimetry. The results indicate that the SRA has a slight retarding effect on hydration of cement, and the hydration of paste with and without the SRA tended to be the same with increasing the curing time. The appearance time of exothermic peak can be delayed, and the peak value as well as the hydration heat of cement can be lowered by adding the SRA. The chemically combined water of the SRA paste is less than that of the controlled sample. A difference of hydration between the controlled paste and the SRA paste is shortened with hydration age. The Ca（OH）2 content of the SRA paste is less than that of the controlled paste at 3 d, but they are similar at 28 d. Furthermore, the pore volume can be reduced and the innocuous pores can be increased by the SRA used. In addition, the resultant formation of the SRA in pore solution of cement-based materials was supposed.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2009年第7期1244-1248,共5页
Journal of The Chinese Ceramic Society
关键词
水泥基材料
减缩剂
水化
孔结构
cement-based materials
shrinkage reducing admixture
hydration
pore structure
