摘要
研究了聚羧酸系高效减水剂是否会对混凝土干缩产生负影响,同时验证了在隧道工程中弃用AFt类膨胀剂而代之以聚羧酸系高效减水剂的可行性和合理性。试验选用聚羧酸系高效减水剂、AFt膨胀剂和镁质膨胀剂,相继对自由收缩试件和两端受限混凝土试件的干缩进行了研究,并进行了不同胶凝材料用量下聚羧酸系高效减水剂和AFt膨胀剂对混凝土干缩的试验。结果表明,与膨胀剂相比,聚羧酸系高效减水剂不会对混凝土干缩性能带来负影响,还可能有一定程度的改善作用。在隧道工程实践中,用聚羧酸系高效减水剂代替AFt类膨胀剂是合理可行的,对混凝土结构的耐久性有利。
In this paper, there is a research about whether the high - performance water reducer like poly - carboxyl acid superplasticizer （ for short, PAS） has the disadvantageous effects on dry shrinkage of concrete and a test of the rationality and feasibility of substituting PAS for the AFt expansion agent in tunnel construction. In this experiment, the high - performance water reducer,AFt EA and magnesic EA are chosen to study the effects of the unconfined concrete specimens, ends- confined ones and the water reducer PAS and AFt EA with different binding materials on the dry shrinkage of concrete. The results indicate that compared with the AFt EA, the PAS won ＇t bring negative effects to the dry shrinkage of concrete but will to some extent improve it instead. In the tunnel engineering, it has proved that replacing AFt EA with PAS is reasonable and will prolong the durability of the concrete structures.
出处
《建材技术与应用》
2008年第1期6-8,共3页
Research and Application of Building Materials
关键词
减水剂
膨胀剂
干缩
自由收缩
限制收缩
water reducer （poly - carboxyl acid superplasticizer： PAS）
expansion agent
dry shrinkage
unconfined shrinkage
confined shrinkage
