再生微粉多元复合胶凝体系的性能研究
Properties of Multi-Component Composite Cementitious System of Regenerated Micropowder
裴军军 1苑博文 2高敏 2郭启龙 1林政红 2黑亚萌2
作者信息
- 1. 西北民族大学土木工程学院,兰州 730124;甘肃省绿色工程材料与低碳建造重点实验室,兰州 730124
- 2. 西北民族大学土木工程学院,兰州 730124
- 折叠
摘要
再生微粉复合胶凝体系对再生微粉的应用具有积极作用.本文采用再生微粉-水泥-粉煤灰构建二元/三元复合胶凝体系,研究了再生微粉的掺量对胶砂试块物理、力学性能的影响,并通过XRD和SEM探究了胶砂试块的水化产物和显微结构.结果表明:随着再生微粉掺量的增加,胶砂试块3、7、28 d的抗压强度逐渐下降,需水量增加,流动度下降,干缩值先减小后增大;掺有再生微粉和粉煤灰的复合胶凝体系胶砂试块的干燥收缩在7～14 d发展较快.随着再生微粉和粉煤灰掺量的增加,水化硅酸钙生成量逐渐减少,胶砂试块内部孔隙、裂隙明显增多.再生微粉和粉煤灰对水泥的总取代率最大为40％(质量分数).
Abstract
Composite cementitious system of regenerated micropowder is beneficial for the application of regenerated micropowder.A binary/ternary cementitious composite system was constructed by using regenerated micropowder-Portland cement-fly ash.The effect of regenerated micropowder content on physical and mechanical properties of mortar test block was studied,and the hydration products and microstructure of mortar test block were investigated by XRD and SEM.The results show that with the increase of regenerated micropowder content,the compressive strength of test block at 3,7 and 28 d decreases,the water demand increases,the fluidity decreases,and the dry shrinkage decreases first and then increases.The drying shrinkage of composite cementitious system mortar test block mixed with regenerated micropowder and fly ash developes rapidly within 7～14 d.With the increase of regenerated micropowder and fly ash content,formation of C-S-H decreases gradually,and the internal pores and cracks of mortar test block increases significantly.The maximum total substitution rate of regenerated micropowder and fly ash to cement is 40％(mass fraction).
关键词
再生微粉/碱激发/复合胶凝体系/力学性能/水化产物/干燥收缩Key words
regenerated micropowder/alkali activation/composite cementitious system/mechanical property/hydration product/drying shrinkage引用本文复制引用
基金项目
甘肃省自然科学基金(20JR5RA510)
西北民族大学引进人才项目(Z14013)
中央高校基本科研业务费专项(31920230028)
出版年
2024
国家科技期刊平台
NSTL
万方数据