粉煤灰对混凝土性能影响的电化学研究

Study on Electric Chemistry Effect of Fly Ash on Concrete Performance

应用3×3矩列丝束电极模拟研究混凝土中钢筋的腐蚀情况。将混凝土试样(空白样和加入粉煤灰的混凝土样)分别都浸泡在1.7mol/LNaCl溶液中,通过测量铁丝束电极的自腐蚀电位,获得了在不同埋置深度时,铁丝腐蚀的电位分布信息。结果表明:(1)普通混凝土中铁丝腐蚀不均匀,自腐蚀电位较分散,电位随时间负移;(2)加入粉煤灰后,铁丝自腐蚀电位负移量减少,腐蚀程度显著下降,因此粉煤灰能有效提高混凝土中钢筋的抗锈蚀能力。

By 3x3 matrix tow electrodes simulated the eroding condition of reinforcing steel bar in concrete. Immersed the concrete samples in 1.7 mol/L NaCl solution, by determining self-eroding potential difference of the iron tows, they got the potential difference＇s distributing information at different depth. The results show that in ordinary concrete, the iron wire erodes asymmetrically and the po- tential difference disperses widely which moves negative with time; and when fly ash is added, the negative move decreases. So we can say that fly ash can improve the erode resistance of the reinforcing steel bar in the concrete.