碳化对粉煤灰水泥石比表面积和孔径的影响

Effect of Carbonation on the Specific Surface Area and Pore Structure of Fly Ash Cement Paste

用COULTERSA3100比表面积和孔径分析仪研究了碳化前后掺粉煤灰水泥石内比表面积和孔径的变化.结果表明,碳化使水泥石中孔径大于20nm的毛细孔体积减小,而孔径小于20nm的毛细孔体积增大,总孔体积减小,但内比表面积增大.水泥浆体的水灰(胶)比越大,碳化对掺粉煤灰水泥石内比表面积和孔径的影响越大.

The specific surface area and pore structure of hardened fly ash-cement paste before and after carbonation were examined by COULTER SA3100 surface area and pore size analyzer. The results show that carbonation reduces pore volume with size of 20～200 nm in hardened cement paste while it increases that with size of smaller than 20 nm. The total pore volume is reduced and the specific surface area is increased. The effect is more significant on hardened cement paste prepared with high mW/mC（or mW/mB） ratio than on that with low mW/mC（or mW/mB） ratio.