Abstract: Based centrifugation and high-pressure extraction, liquid phase of cement-fly ash system between 0—1 h and 5—24 h were extracted respectively. In order to explore the influence from different dosage of fly ash on the ion concentration and the conductivity in liquid phase of system, the ion concentration and electrical conductivity were analysed by inductively coupled plasma optical emission spectrometry (ICP-OES), pH meter and conductivity meter. The results show that along hydration time, K+ concentration present downward trend firstly and then increased gradually, Na+ and SiO44- concentration and pH increased gradually, Ca2+ and SO42- concentration present on the contrary with K+ concentration reaching the peak value around 5 h, AlO2- concentration present similarly with Ca2+ and SO42- concentration arriving the peak value around 10 h. Ions concentration and conductivity in liquid phase of cement-fly ash system are decreased along with the increasing dosage of fly ash(0%,10%,30% and 50%), and three stages (dissolution, induction, and acceleration) during the early hydration of cement-fly ash system are identified according to the characteristics of the laws of liquid conductivity change. Liquid conductivity are positively correlated with the total ion concentrations, mainly affected by K+, Na+ and OH-, and the relationships between single ion and the liquid conductivity are influenced significantly by high dosage(50%) of fly ash.
钱如胜,张云升,张宇,杨永敢. 水泥-粉煤灰体系早龄期液相离子浓度与电导率的关系[J]. 《材料导报》期刊社, 2018, 32(12): 2066-2071.
QIAN Rusheng, ZHANG Yunsheng, ZHANG Yu, YANG Yonggan. Relationships Between Liquid Ion Concentration and Electrical Conductivity During the Early Hydration of Cement-Fly Ash System. Materials Reports, 2018, 32(12): 2066-2071.
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2018, Vol. 32 
