混凝土减缩剂的制备与研究

Preparation and research of concrete shrinkage reducing agent

通过对5种单一减缩组分进行分散性能、表面张力、混凝土性能试验,选取2种减缩性能较好的减缩组分进行不同比例的复合,制备了混凝土复合减缩剂P-3。并采用扫描电镜和微量热仪研究了减缩剂对水泥净浆水化的影响,进而对减缩剂的作用机理进行了研究。试验结果表明,该减缩剂能大幅度降低水溶液的表面张力,同时对混凝土具有较好的减缩效果,当掺量为0.5%时,7 d混凝土减缩率达37%,28 d减缩率为35%,且该减缩剂对混凝土强度影响不显著。

Through the dispersion performance,surface tension,and concrete performance tests of five single shrinkage reduction components,two kinds of shrinkage reduction components with better shrinkage performance were selected for compounding in different proportions to prepare a concrete composite shrinkage reducing agent P-3.The effect of shrinkage reducing agent on cement slurry hydration was studied by scanning electron microscope and microcalorimeter,and then the mechanism of shrinkage reducing agent was studied.The test results show that,the shrinkage reducing agent can greatly reduce the surface tension of the aqueous solution and has a good shrinkage reduction effect on concrete.When the mixing amount was 0.5%,the 7 d concrete shrinkage rate reached 37%,and the 28 d shrinkage rate was 35%.The impact of shrinkage reducing agent on concrete strength was not significant.