纳米颗粒对超低水胶比复合水泥浆体水化和孔结构的影响

Influence of nano- particles on hydration and pore structure of compounded paste with very low water- binder ratio

为掌握纳米颗粒材料对超低水胶比水泥基材料水化与微结构的影响规律,采用热重分析法和BET测孔方法测试分析nano-Si O2,nano-Al2O3,nano-Fe2O3及nano-Ca CO34种纳米颗粒对超低水胶比复合水泥浆体结合水含量与孔隙结构的影响,并探讨相应的机理。研究结果表明:相对于普通水泥体系,上述4种纳米颗粒更显著地促进了超低水胶比复合水泥浆体的水化进程,且存在最佳的纳米颗粒掺量,使得超低水胶比浆体28 d龄期的结合水量最大;纳米颗粒可有效改善超低水胶比复合水泥浆体的孔隙结构,降低其总孔隙体积和平均孔径,很好地发挥了纳米尺度充填密实作用。纳米颗粒在制备超低水胶比高性能水泥基材料具有显著的优势。

For the sake of understanding the effects of nanoparticles on hydration and microstructure of cement-based materials with very low water to binder ration,the chemically bound water and pore structure of cement paste with very low water-binder ratio incorporating four nanoparticles of nano-SiO2,nano-Al2O3,nano-Fe2O3 and nano-CaCO3 were investigated by TG and BET experimental methods,respectively.Results show that the incorporation of aforemen-tioned nano-particles plays more significant role in promoting the hydration process of paste with very low water to binder ratio as compared to the ordinary cement paste.Due to the nano-scale filling role,the porosity and average pore diame-ter of samples can be reduced by adding nanoparticles.It proves obvious advantage in preparing high performance cement-based materials with very low water to binder ratio by utilizing nanoparticles.