地质聚合物修复材料在海水中的性能演化%Performance evolution of geopolymer repair materials in seawater
国电电力广东新能源开发有限公司 河南省科学院
2026-03-17
矿渣基地质聚合物 偏高岭土 海水侵蚀 氯离子含量
[目的]矿渣基地质聚合物具有良好的耐化学侵蚀性能,但在实际应用过程中存在局限性.掺入低活性偏高岭土可改善其施工性能,提高其抗侵蚀性能.[方法]以矿渣和偏高岭土为原料,水玻璃为激发剂,制备了矿渣/偏高岭土地质聚合物,考察了海水侵蚀条件下其力学性能、氯离子含量和产物组成,并进行了热重分析.[结果]加入适量的偏高岭土可以增加矿渣基地质聚合物遭海水侵蚀后的力学性能.当偏高岭土掺量为10%时,180 d海水侵蚀后矿渣基地质聚合物的抗折强度和抗压强度分别提升了13.5%和5.9%.而且与纯矿渣基地质聚合物相比,其总氯离子含量、自由氯离子含量及结合氯离子含量都更低.海水侵蚀后,地质聚合物样品5 mm深度以内的表层生成了Mg(OH)2沉淀,导致致密性提高,令其与海水中侵蚀性离子的相互作用减少.[结论]结合矿渣地质聚合物自身在侵蚀环境中的稳定性,偏高岭土的掺入使得地质聚合物具有更好的耐海水侵蚀能力.%[Objective]Slag-based geopolymers exhibit good resistance to chemical erosion,but they have limitations in practical applications.Incorporating low-reactivity metakaolin can improve their workability and enhance their erosion resistance.[Method]Slag/metakaolin geopolymers were prepared with water glass as an activator.Their mechanical properties,chloride ion content,and product composition under seawater erosion conditions were studied,accompanied by thermogravimetric analysis(TGA).[Result]The addition of an appropriate amount of metakaolin increased the mechanical properties of slag-based geopolymers after seawater erosion.At a metakaolin content of 10%,the flexural strength and compressive strength of the slag-based geopolymer after 180 days of seawater exposure increased by 13.5%and 5.9%,respectively.Furthermore,compared to the metakaolin-free slag-based geopolymer,its total chloride ion content,free chloride ion content,and bound chloride ion content were all lower.After seawater erosion,Mg(OH)2 precipitate formed on the surface layer within 5 mm depth of the geopolymer samples,leading to increased compactness and reduced interaction with aggressive ions in seawater.[Conclusion]Combined with the inherent stability of slag-based geopolymer in erosive environments,the incorporation of metakaolin endows the geopolymer with superior resistance to seawater erosion.
