偏高岭土复合灌浆材料是一种在水泥中大比例掺入偏高岭土的无机灌浆料,被应用于石窟岩体裂隙防渗灌浆工程领域.本文通过水化热、XRD、FTIR、SEM-EDX测试手段研究了二元和三元偏高岭土复合灌浆材料的水化过程及产物特征,并结合力学性能及水溶盐测试分析了该材料应用于石窟裂隙灌浆的可行性.结果表明,大比例掺入偏高岭土的水泥材料反应程度较低,但偏高岭土的稀释效应、火山灰反应以及活性Al的电荷补偿效应对降低水溶液盐碱含量起到积极作用.硅灰的掺入能提升三元复合灌浆材料的水化程度及力学强度,然而水化产物Al/Si的降低不利于K+、Na+吸附.偏高岭土复合灌浆材料在石窟水害治理中是一种相比普通硅酸盐水泥更加安全的材料,与石窟环境具有更好的兼容性;作为辅助胶凝材料,偏高岭土在减少K+、Na+浸出方面相比硅灰更有优势.
Metakaolin composite grouting material is an inorganic grouting material mixed with a large proportion of metakaolin in cement,which is used for anti-seepage grouting engineering of rock fissures in grottoes.In this paper,the hydration and product characterization of binary and ternary metakaolin composite grouting material were studied by means of hydration heat,XRD,FTIR,and SEM-EDX test.The feasibility of applying this material to grotto fissure grouting was analyzed by mechanical properties and water-solube salt test.The results indicate that the reaction degree of cement materials with is low.But the dilution effect and pozzolanic reaction of metakaolin and the charge compensation effect of active Al have a significant advantage in reducing the salt and alkali content in leaching solution.The addition of silica fume can enhance the hydration degree and mechanical strength of ternary composite grouting material.However,the decrease in Al/Si of hydrated products is not conducive to the adsorption of K+and Na+.The metakaolin composite grouting material is a safer material than ordinary Portland cement in grotto protection,and it exhibits better compatibility with grottoes environment.Additionally,metakaolin,as a supplementary cementitious material,has more advantages over silica fume in reducing K+and Na+leaching.