水泥基渗透结晶型防水材料的制备及性能

Preparation and Properties of Cement-based Permeable Crystalline Waterproof Materials

基于以膨润土、甲基硅酸钠等为原料自主研制的活性增强剂B-SMC,采用在碱性渗透剂中添加与不添加B-SMC制备水泥基渗透结晶型防水材料(B-SMC-1,B-SMC-0),研究B-SMC对防水材料基本和自愈合性能的影响,且对其物相组成和微观形貌进行分析。结果表明:活性增强剂B-SMC可提升防水材料的基本和自愈合性能,试件B-SMC-1的抗压与抗折强度、湿基面黏结强度、抗渗与自愈合性能均优于B-SMC-0和成品C试件,且满足GB 18445—2012《水泥基渗透结晶型防水材料》的指标要求;B-SMC-1试件中未水化的硅酸二钙、硅酸三钙被B-SMC活性增强剂激发,络合生成亚稳态的钙离子络合物,钙离子络合物与裂缝引入的CO_(3)^(2-)及HCO_(3)^(-)反应生成碳酸钙晶体,碳酸钙晶体与C-S-H凝胶、钙矾石进行复合,有效弥合裂缝,显著提升B-SMC-1试件的自愈合性能。

An active enhancer B-SMC was independently developed based on bentonite and sodium methylsilicate, and then the cement-based permeable crystalline waterproof materials of B-SMC-0 and B-SMC-1 were prepared with or without B-SMC in alkaline penetrant.The effects of B-SMC on the basic and self-healing properties of waterproof materials were studied, and their phase composition and micro morphology were analyzed. The results show that the active enhancer B-SMC can improve the basic and self-healing properties of waterproof materials, and the compressive and flexural strength, wet base surface bonding strength, permeability resistance and selfhealing properties of B-SMC-1 are better than those of specimen B-SMC-0 and finished product C, and meet the index requirements of GB 18445—2012 Cement-based Permeable Crystalline Waterproof Materials. The unhydrated two calcium silicate and three calcium silicate were excited by the active enhancers B-SMC to form metastable calcium complexes, and the calcium complexes react with the CO_(3)^(2-)and HCO_(3)^(-)introduced by the cracks to form calcium carbonate crystals. The calcium carbonate crystals are combined with C-S-H gel and albite to effectively bridge the cracks, which can significantly improve the self healing properties of B-SMC-1 specimen.