细砂增强偏高岭土基地质聚合物力学性能细观研究Mesoscopic Study on Mechanical Properties of Metakaolin-based Geopolymer Reinforced by Fine Sand
王忠昶;赵晓昀;
摘要(Abstract):
为提高偏高岭土基地质聚合物力学性能,制备了掺有标准砂及细砂的地聚物复合物.设置对比组,通过无侧限抗压测试及PFC(3D)颗粒流模型研究了细砂粒径及掺入量对偏高岭土基地聚物力学性能的影响.结果表明:15%最大质量分数的标准砂可以小幅提高地聚物的抗压强度,在室温环境下养护28 d后试件强度达到25.40 MPa.细砂可以大幅提高地聚物的抗压强度,减少复合物内部微裂隙,减轻颗粒破坏程度,且细砂粒径越小,效果越显著.当掺入粒径小于0.15 mm,最大质量分数为15%的细砂时,复合物强度达到41.51MPa.随着细砂掺入量的增加,试件内部出现大量广泛分布的裂纹,孔隙度变化程度减小,抗压强度下降.
关键词(KeyWords): 偏高岭土;细砂;抗压强度;地质聚合物
基金项目(Foundation): 国家自然科学基金资助项目(51574055)
作者(Authors): 王忠昶;赵晓昀;
DOI: 10.13291/j.cnki.djdxac.2022.01.016
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