吸水树脂改善自密实混凝土干缩性能的研究

Influence of absorbent polymer on improving shrinkage of self-compacting concrete

自密实混凝土干缩问题严重影响了其耐久性,通过引入吸水树脂预吸水对混凝土进行内部养生,对混凝土的干缩率降低效果显著,与普通自密实混凝土相比,固定水灰比为0.36、0.34、0.32时,内养生自密实最大干缩率分别降低了89.2%、87.8%、82.2%。当固定树脂掺量时,自密实混凝土干缩率降低效果与水灰比大小存在相关性,树脂掺量为0.1%时,干缩率降低效果好的水灰比为0.34,树脂掺量为0.2%时,水灰比取为0.36较佳,而树脂掺量为0.3%时,则水灰比为0.34的混凝土干缩率降低明显。试验结论对于指导吸水树脂内部养生自密实混凝土的设计和使用具有重要的价值。

Shrinkage ofself-compacting concrete seriously affect its durability.In this investigation,internal curing of self-compacting concrete was internally cured by introducing anabsorbent polymer.The results showed that the dry shrinkage of concrete reduced signifi- cantly.Compared with the ordinary self-compacting concrete, on the condition of fixing water cement ratio of 0.36,0.36,0.36, maximum dry shrinkage of internal curing self-compacting were reduced by 89.2%, 87.8% and 89.2% respectively.When fixed absorbent polymer content, shrinkage reducing rate self-compacting concrete have a correlation with water-cement ratio.The dosage of the absorbent polymer were 0.1% ,0.2% ,0.3%, shrinkage reducing rate of concrete were more obvious for the 0.34,0.36,0.34 water-cement ratio.The results are of great valuefor guiding the mixing design and application of internal curing self-compacting concrete.