基于直/交流电试验方法的水泥基材料渗透性

Chloride permeability in cement-based materials based on DC/AC methods

基于直流电通量和交流阻抗谱等2种电学测试方法,该文研究了水灰比和预处理方式对水泥基材料电学性质的影响,2种电学方法的试验结果表明：随着水灰比的增大,水泥基材料的直流电通量和交流连通孔隙电阻增大,抗氯离子渗透能力降低;饱水和饱盐2种预处理方式对直流电通量影响不大,测试得到的电通量和初始电流结果基本一致,但对交流阻抗谱试验而言,饱盐试件测得的电阻值较饱水试件低;连通孔隙电阻与电通量呈指数关系,而连通孔隙电阻与初始电阻则呈线性关系;对于饱盐预处理水泥基材料,可以结合初始电流和电通量综合评价水泥基材料的抗氯离子渗透性。

The chloride permeability of cemented materials saturated with solutions of deionized water or 1 mol/L NaCl was measured using the rapid chloride permeability test（RCPT）and electrical impedance spectroscopy（EIS）. The results show that as the water-cement ratio increases,the passed charge and the resistance of continuous conduction paths（R1）increase,indicating that a reduced anti-chloride penetration ability.The RCPT tests showed that the passed charge and temperature rise of the specimens saturated with different solutions were almost the same for a given water-cement ratio.However,the EIS tests showed that the initial currents in the NaCl saturated samples were higher than in the water saturated samples.DC/AC tests showed a strong power relation between R1 and the passed charge and a linear relationship between R1 and the passed initial current.Thus,the initial current can be used to calculate the chloride diffusion coefficient and to evaluate the permeability more accurately with the passed charge.