新型聚合物内养护材料对高强混凝土自收缩影响研究

摘要

Internal curing has become a hot topic in mitigating autogenous shrinkage of high strength concrete, HSC.In this thesis,relationship between autogenous shrinkage and new internal curing materials was carried out and internal curing mechanism was further investigated.The results show ICA that provides useful refer-ence for solving early-age shrinkage.When the amount of ICA 20 to 25 kg/m3 ,the particle diameter below 100μm,autogenous shrinkage of HSC was well mitigated.When manganese slag powder and fly ash in concrete, its can play an assembling role on internal curing as ICA.MIP analysis confirmed that mitigation of autogenous shrinkage lies in reducing the amount of shrinkage adversely 9-50 nm capillary pores,and increasing the number of below 9 nm gel pores by internal curing.%内养护(internal curing)是抑制高强混凝土自收缩研究的热点。研究了新型内养护材料对高强混凝土自收缩的影响规律，通过孔结构分析了内养护作用机理。结果表明，内养护材料用量20~25 kg/m3、粒径<100μm时，抑制自收缩效果较佳。当混凝土中有锰渣微粉和粉煤灰时，内养护材料(internal curing agents)可与之发挥协同抑制效应。压汞分析证实，内养护减少了混凝土中对收缩不利的9~50 nm 毛细孔数量，增加了9 nm以下凝胶孔数量。