A MULTI-SCALE INVESTIGATION ON THE EFFECT OF VISCOSITY MODIFYING ADMIXTURES ON THE FLOWABILITY AND STABILITY OF SELF COMPACTING CONCRETE
Self compacting concrete, due to its high flowability, may suffer from different signs of instability such as bleeding, blocking and segregation, during transportation and placement.Viscosity modifying admixtures (VMAs), also called segregation reducing agents or anti-washout admixtures, have been extensively used in self compacting concrete for their effects on the stabilizing rheological properties of fresh concrete. The applied VMAs are in various types and their effects are widely varied according to their chemical structures. In this study, the effect of two types of VMAs on the fluidity, viscosity and stability of self compacting concrete was investigated. The experimental investigation was carried out in two phases: cement paste and mortar originated from self compacting concrete and the same trend was observed in all the cases. The obtained results show that some types of VMAs mainly affect the stability of self compacting concrete while having no effect on the viscosity.It was also concluded that using VMAs may decrease the fluidity of self compacting concrete which might be compensated with addition of superplasticizer content or W/C ratios.
Self compacting concrete Viscosity modifying admizture Flowability Viscosity Stability
Mohammad Shekarchi Nicolas Ali Libre Rahil Khoshnazar Solmaz Dehghan Marvasty Reza Rashet Nia
Construction Materials Institute,Department of civil Engineering,Faculty of Engineering,University of Tehran,Tehran,Iran
国际会议
长沙
英文
303-311
2009-06-05（万方平台首次上网日期，不代表论文的发表时间）