Percolating and the equivalent electrical circuit of cement - based conductive composite are analyzed . the characteristics of the lower percolation are found out . a new way to determine the lower percolation is proposed . carbon fiber reinforced cement and graphite conductive cement are studied to identify the new way . it is found that the new way is precise and convenient to determine the lower percolation of cement - based conductive composite 从理论上分析了水泥基导电复合材料的渗滤过程及其等效电路，得出了导电材料含量达到下阈值时的特征，提出了一种新的判定水泥基导电材料下阈值的方法，并用碳纤维增强水泥和石墨导电水泥进行了验证，发现这种新方法可以方便准确地确定水泥基导电复合材料的下阈值。
