Effects of Organosilane-modified PCE on the Fluidity and Hydration Properties of Cement-Fly Ash Composite Binder

何燕^1,2,3，LIU Shuhua^4,5，JI Tao⁶，SHUI Liangliang⁸

1. School of Civil Engineering, Suzhou University of Science and Technology2. State Key Laboratory of Green Building Materials, China Building Materials Academy3. State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology4. Hubei Key Laboratory of Water System Science for Sponge City Construction, Wuhan University5. State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University6. School of Architecture and Engineering, Nanjing Institute of Technology8. Shanghai Municipal Engineering Design Institute(Group) Co. Ltd.

摘 要：Effects of organosilane-modified PCE （OS-PCE） on the fluidity and the hydration properties of cement-fly ash （FA） composite binder were systematically analyzed.The experimental results show that OS-PCE possesses respectively 36.98% and 36.67% higher saturated adsorption amount on cement and FA,in comparison with ordinary PCE,and can contribute to higher fluidity of cement-FA composite binder.The addition of OS-PCE retards hydration process of cement-FA composite binder proportionally with the dosage of OS-PCE,but promotes the hydration kinetics of the composite binder.The reactivity enhancement is attributed to the well-dispersed FA by OS-PCE,which provides more nucleation sites for the reaction of heterogeneous C-S-H and enhances the contact with water to react with CH forming pozzolanic C-S-H.Well-distributed hydration products are exhibited in the hardened binder added with OS-PCE,with a large number of hydrated gels uniformly fill in the pores and gaps,which improves the compaction of the hardened structure.

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