减水剂对水泥水化产物微观形貌的影响

Effects of Water-reducing Agents on Micropattern of Cement Hydration Products

研究木素磺酸钙、改性木素磺酸钙、萘磺酸甲醛缩合物、氨基磺酸甲醛缩合物和三聚氰胺脲醛树脂5种减水剂对水泥水化产物微观形貌的影响。结果表明,掺木素磺酸钙的水泥石中生成较多短柱状钙矾石(AFt);掺改性木素磺酸钙的水泥石中短柱状和长柱状AFt交错生长;掺萘磺酸甲醛缩合物、氨基磺酸甲醛缩合物和三聚氰胺脲醛树脂可分别使水泥石中AFt呈长杆柱、波浪状和规则六方柱状生长。当水化龄期达到60d时,0.8%木素磺酸钙、改性木素磺酸钙的水泥石中出现连通孔洞;掺0.8%萘磺酸甲醛缩合物和氨基磺酸甲醛缩合物造成水泥石中出现微裂缝;掺加0.4%三聚氰胺脲醛树脂和改性木素磺酸钙的水泥石结构致密。减水剂的分散性、引气性和缓凝性是其对水化产物微观形貌影响的主要原因。

The effects of five kinds of water-reducing agents：calcium lignosulfonate, modified calcium lignosulfonate,amino-sulfonic based superplasticizer, sulfonated naphthalene formaldehyde and sulfonated melamine urea formaldehyde resin on the micropattern of cement hydration products were studied. The research results indicate that cement stone mixed with calcium lignosulfonate created short columnar AFt; cement stone mixed with modified calcium lignosuifonate created short columnar AFt interlaced with long columnar AFt. Mixing with sulfonated naphthalene formaldehyde and amino-sulfonic based superplasticizer may help AFt in cement stone grow like long poles and waves;AFt in cement stone mixed with sulfonated melamine urea formaldehyde resin normally shaped hexagonal column. With increasing of age, when hydration reached 60 d, connective pores would appear within lignosulfonate and modified calcium lignosulfonate;slight cracks 0.8% sulfonated naphthalene formaldehyde and amino-sulfonic cement stone mixed with 0.8% calcium will appear within cement stone mixed with based superplasticizer; the micropattern of cement stone mixed with 0.4% sulfonated melamine urea formaldehyde resin and modified calcium lignosulfonate was close-grained.