四元水滑石碳纳米管在水泥净浆中对硫酸根离子的固化性能

The Curing Properties of Quaternary Hydrotalcite Carbon Nanotubes for Sulfate Ions in Cement Paste

为了提高混凝土结构抗硫酸盐侵蚀,采用共沉淀法制备钴铁镁铝四元水滑石,采用固相混合法制备钴铁镁铝水滑石-碳纳米管复合材料。将其应用于水泥净浆中,研究了龄期、浓度对固化硫酸根离子性能的影响,结果表明:和普通水泥净浆相比,加入钴铁镁铝水滑石-碳纳米管后,对SO^(2-)_(4)固化能力得到了明显的提升,在7 d,SO^(2-)_(4)浓度为0.05 mol/L时,其固化量由97.46 mg/g增加到107.11 mg/g;CoFeMgAl-LDHs/CNTs本身对SO2-4固化量随着SO2-4浓度的增加而增加,在SO^(2-)_(4)浓度为0.5~1.5 mol/L时,固化量增长较为平缓,在1.5~2.5 mol/L时,固化量增长较快;固化量随着龄期的增加而增加。

In order to improve the resistance of concrete structure to sulfate attack,cobalt-iron-magnesium-aluminum tetrabasic hydrotalcite was prepared by coprecipitation method,and cobalt-iron-magnesium-aluminum hydrotalcite-carbon nanotube composite was prepared by solid phase mixing method.The effect of curing time and concentration on the properties of sulfate ion in cement paste was studied.The results showed that:compared with the ordinary cement paste,after adding cobalt-iron-magnesium-aluminum hydrotalcite-carbon nanotubes,when the concentration of SO^(2-)_(4) is 0.05 mol/L,the amount of SO^(2-)_(4)curing increases from 97.46 mg/g to 107.11 mg/g,and the amount of SO2-4 curing CoFeMgAl-LDHs/CNTs increases with the concentration of SO2-4,when the concentration of SO^(2-)_(4)was 0.5-1.5 mol/L,the amount of cure increased slowly,and quickly at 1.5-2.5 mol/L,the amount of cure increased with the increase of age.