碳酸盐粉煤灰水泥复合胶凝材料浆体的电学特性

Electrical property of complex binder paste with carbonate-fly ash-cement

采用循环伏安法和交流阻抗法研究了碳酸盐粉煤灰水泥复合胶凝材料浆体的电阻率和交流阻抗等电学特性.结果表明:碳酸盐掺合料能够提高复合胶凝材料浆体的电阻率,碳酸盐和硅微粉惰性掺合料对复合胶凝材料浆体电阻率的贡献率大于粉煤灰和偏高岭土活性掺合料;碳酸盐掺合料降低了表征浆体C-S-H胶凝中导电离子的电容(Cg);提高了表征复合胶凝材料浆体孔隙率的高频电阻(Rs),即降低了浆体孔隙率;提高了表征浆体水化程度的低频电阻(Rct).

The electrical properties such as electrical resistivity and AC impedance of complex binder paste system containing carbonate, fly ash and cement were studied by the methods of Cyclic Voltammerry and AC Impedance Spectroscopy. The results show that carbonate admixture could increase the electrical resistivity of paste. The contribution rate for electrical resistivity of inert mineral admixtures （carbonate, silica powder） to the paste is higher than that of active mineral admixtures （fly-ash, metakaoline）. Carbonate admixture can reduce the electric capacity （Cg） of the paste, characterizing conductive ionic in C-S-H gel, and increase the high frequency resistivity （Rs） , characterizing porosity of complex binder paste, in other words, the porosity of paste is decreased. Carbonate admixture can also enhance low frequency resistivity （Rct） which characterizes the hydration deuree of paste.