电化学参数对混凝土除氯效率的影响

Influence of electrochemical parameters on chloride extraction efficiency

为确定氯盐污染混凝土结构的最佳电化学除氯参数,对掺3%水泥质量NaCl的混凝土圆柱体试件进行电化学除氯实验,研究了3种不同电流密度(1、2、3A/m2)和3种不同电解液(自来水、饱和Ca(OH)2溶液、Na3BO3为0.1mol/L)作用下的氯离子排出量随时间的变化规律.结果表明:电流密度越大,通电开始6d内混凝土的除氯速率越快;28d的总除氯量越多,钢筋附近混凝土微观结构劣化和碱性物质富集越多.因此,确定2A/m2为最佳电流密度.相同电流密度通电28d后,自来水中的除氯量大约只有其他2种电解液的50%,因此,应采用碱度较高的饱和Ca(OH)2溶液或物质的量浓度Na3BO3为0.1mol/L的电化学除氯电解液.

In order to determine the optimal parameters of electrochemical chloride extraction ( ECE) treatment on the concrete structure contaminated by chloride,ECE treatment was applied to the cylindrical concrete specimens containing NaCl of 3% cement mass.The variation of chloride extraction content with time was studied at three different current densities of 1,2 and 3 A /m2 as well as in three different electrolyte solutions including tap water,saturated Ca( OH) 2 solution and 0.1 mol/L Na3BO3 solution.The resu...