三组分胶凝材料体系的交流阻抗特性

AC Impedance Characteristics of Ternary Cementitious Materials

由于地铁在运行过程中产生的杂散电流会造成钢筋混凝土中钢筋的电化学腐蚀,从而影响地铁混凝土结构的耐久性。在配制混凝土时,用矿渣和粉煤灰取代一部分水泥,可明显改善胶凝材料硬化浆体的孔结构,降低孔溶液中的离子浓度,从而提高混凝土的电阻率。提高混凝土的电阻率可在一定程度上减缓钢筋的腐蚀。使用三组分胶凝体系研究方法,对水泥、粉煤灰和矿渣组成的三组分胶凝体系的交流阻抗特性和电阻值进行了研究和分析,得到不同龄期的阻抗等值线图。研究表明,当三组分胶凝体系中粉煤灰和矿渣总量在50%～65%的范围,且两者得比例为1左右时,三组分胶凝材料砂浆的电阻率最大。

During the operation of subway, stray current has negtive effects on the durability of concrete. In the preparation of concrete, use of fly ash and slag to replace some cement can increase the resistance of concrete and corrosion resistance of steel in the concrete. This study investigated the impedance characteristics of ternary cementitious materials and obtained the electrical resistance contours of the materials at different ages. It was found that when total content of fly ash and slag powder was in the range of 50%-65% and fly ash to slag content ration was around 1, mortars made with the ternary cementitious material demonstrated the highest resistance.