多酸复合作用对溶液型液体无碱速凝剂性能影响研究

Research on the effect of multi-acid compound action on the performance of solution-type liquid alkali-free accelerator

溶液型液体无碱速凝剂AF-LR-FSA因其促凝效果好、绿色环保等优势,已成为当前喷射混凝土技术的研究热点。然而AF-LR-FSA中重要促凝成分硫酸铝极易从水相体系中析出,严重影响其稳定性。选择多种酸作为稳定剂,研究了单一酸和多种酸对AF-LR-FSA稳定时间、水泥砂浆凝结时间和强度的影响。结果发现,体系中含2种及以上有机酸可提高产品稳定性,其中1种有机酸为抗坏血酸(VC)时稳定性更好,稳定时间最长可达到180 d。

Due to its effective setting accelerator effect and environmental protection,the solution-type liquid alkali-free accelerator(AF-LR-FSA)has emerged as a research focus in the field of shotcrete.However,the performance stability of AF-LR-FSA is significantly impacted by the ease with which aluminum sulfate,an essential coagulation-promoting component,precipitates from the water phase system.The effects of a single acid or multiple acids on the stability time,cement slurry setting time,and strength of AF-LR-FSA were investigated after several acids were chosen as stabilizers.The outcomes demonstrated that the stability of the product is improved in systems with two or more organic acids.When one of the organic acids is ascorbic acid(VC)the stability is better and can last up to 180 days.