偏高岭土、粉煤灰和矿渣地聚合物注浆材料研制与应用

Development and Application of Metakaolin,Fly Ash and Slag Geopolymer Grouting Material

为实现非开挖修复道路结构深层病害,恢复路基承载能力;以水玻璃和碱为碱激发剂,利用偏高岭土、粉煤灰、矿渣制备地聚合物注浆材料,通过力学性能和工作性能试验,以及经济性指标分析,寻找最优的原材料组合。试验结果表明:三者合适的配比为偏高岭土30%~40%,粉煤灰30%~40%,矿渣20%~30%。用水玻璃做碱激发剂,当固含量较小时(24%~32%),相同模数下水玻璃溶液中,K^(+)相对Na^(+)具有更高的反应活性,能够提高浆液的流动度,并提高固化物早期强度。由于硅酸钾水玻璃价格昂贵,在硅酸钠水玻璃中加入KOH制备的KOH/Na_(2)SiO_(3)溶液具有相似的效果。最佳碱激发剂KOH/Na_(2)SiO_(3)溶液的主要参数如下:固含量约为24%、模数为1.2~1.3、液固比为0.65。工程实践表明,研制的地聚合物注浆材料具有良好填充效果。

Three kinds of common industrial raw materials fly ash,metakaolin,slag,used to prepare geopolymer grouting materials for trenchless repair of deep road diseases,with water glass and alkali as activator.Based on the engineering application of grouting materials,taking mechanical properties,working performance and economy into account,the optimal combination of raw materials is founded fly ash 30%~40%,metakaolin 30%~40%,slag 20%~30%.Water glass use as activator,When the solid content is small(24%~32%),K^(+)has higher reactivity than Na^(+)under the same modulus,which can improve the fluidity of the slurry and improve the early strength of the solidified product.With the price of potassium sodium silicate is high,and the preparation of Na_(2)SiO_(3)/KOH solution by adding KOH to sodium silicate has similar effect.The optimum alkali activator is Na_(2)SiO_(3)/KOH solution with solid content of about 24%,modulus of about 1.2~1.3,and liquid-solid ratio of 0.65.The engineering practice shows that the geopolymer grouting material developed in this paper has good filling efficiency.