复掺内养护材料与膨胀剂对C60自密实混凝土性能的影响

Influence of internal curing materials and expansive agent on properties of the C60 of self compacting concrete

研究了单掺膨胀剂以及复掺膨胀剂与内养护材料(AN-ICA)对C60自密实混凝土工作性能、力学性能、体积稳定性能与抗裂性能的影响机制。结果表明:与单掺膨胀剂相比,复掺膨胀剂与AN-ICA的混凝土自收缩率与干燥收缩率显著降低,抗裂性能提高,随着AN-ICA掺量的增加,混凝土的收缩率降低幅度增大,膨胀剂对混凝土的补偿收缩作用增强。利用超分散降黏、减缩保坍的高性能减水剂和内养护材料AN-ICA与II型硫铝酸钙-氧化钙型膨胀剂复掺,制备出适于沪通长江大桥超高桥塔的低收缩抗裂C60自密实混凝土。

The influence mechanism of a single doped expansive agent and combined admixture of expansive agent and internal curing material（ AN -ICA） on workability, mechanical property, volume stability and crack resistance of the C60 self - compacting concrete was studied.The results showed that：the autogenous shrinkage and drying shrinkage of concrete with combined admixture of expansive agent and AN - ICA were greatly reduced compared with the single doped expansive agent concrete ,the decreased degree of shrinkage and crack resistance property were improved with the increasing content of AN - ICA, the effect of expansive agent was better when u- sing combined admixture.With the admixing of ultra - dispersion viscosity and shrinkage reducing slump retaining high performance wa- ter reducing agent, internal curing material AN - ICA and type II of Sulphoaluminate - Calcium oxide expansive agent, the C60 of self - compacting concrete with low shrinkage and crack resistance property was prepared to suit the high Tower of Hu Tong Yangtze River Bridge.