羟乙基甲基纤维素影响水泥水化进程的交流阻抗研究

Study of Hydration Process of Cement Paste Modified with Hydroxyethyl Methyl Cellulose by AC Impedance Spectroscopy

采用交流阻抗谱测试方法,研究了羟乙基甲基纤维素对水泥水化进程的影响规律.研究表明,交流阻抗谱图及其阻抗参数能在一定程度上反映掺羟乙基甲基纤维素水泥浆体的水化进程情况.羟乙基甲基纤维素能显著延缓阻抑水泥水化进程,降低水泥水化程度和水化产物CSH凝胶的生成速率,且能增大水泥浆体的孔溶液黏度,降低孔溶液离子迁移速率,从而导致水泥浆体的电化学反应显著滞后于其水化反应,还能使得水泥浆体孔结构更为简单、均匀;掺量越大,羟乙基甲基纤维素对水泥水化进程的影响程度越大.

The hydration processes of cement pastes modified with hydroxyethyl methyl cellulose（HEMC） were studied by AC impedance spectroscopy. The results show that the hydration process of cement pastes modified with HEMC can be revealed by AC impedance spectroscopic spectrum and parameters. Addition of HEMC greatly retards the hydration process of cement paste, reduces the cement hydration degree, and delays the formation of CSH gel. It can also increase the pore solution viscosity and decrease the pore solu- tion ions migration rate. Thus, the electrochemical reaction of cement paste modified with HEMC lags be- hind its hydration reaction. Moreover, with increase of HEMC use level, the hydration degree of cement gradually decreases, and the pore structure of cement pastes tends to have three-dimensional structure and be much simpler and more uniform.