CMK复合微粉对盐渍土物理力学性能的影响
Effect of CMK Composite Powder on Physical and Mechanical Properties of Saline Soil
樊亚男1
作者信息
- 1. 太原学院 建筑与环境工程系,山西 太原 030032
- 折叠
摘要
以山西运城南部地区盐渍土为研究对象,采用煤系偏高岭土(coal metakaolin,CMK)、矿粉(mineral powder,MP)及水泥(ordinary portland cement,OPC)作为多元复合改良微粉,针对不同养护龄期下改良盐渍土的无侧限抗压强度试验、渗透试验、固结结构物含量试验及扫描电镜(scanning electron microscope,SEM),探讨不同 CMK 复合微粉掺量对盐渍土物理力学性能的影响规律及作用机理.研究结果表明:低掺量(质量分数)煤系偏高岭土-矿粉-水泥复合胶凝材料可以显著提高盐渍土的无侧限抗压强度,且随龄期延长呈不断提高趋势,其中掺加 2%CMK,6%MP,2%OPC时效果最优.固结结构物含量可以作为一项综合指标,反映盐渍土性能,其与无侧限抗压强度和渗透系数可建立良好的线性相关关系.SEM 试验表明,盐渍土改良后,其微观结构得到改善,缺陷率降低,更为致密.
Abstract
Taking the saline soil in the southern area of Yuncheng,Shanxi Province as the re-search object,the study used coal metakaolin(CMK),mineral powder(MP)and cement(OPC)as the multifunctional composite modified micropowder to explore the effect of different dosages of CMK composite micropowder mixing on the physical and mechanical properties and the func-tioning mechanism of modified saline soil.Unconfined compressive strength test,infiltration test,consolidated structural matter content test and microscopic scanning electron microscope(SEM)test were performed on modified saline soil under different maintenance ages.The results show that the low dosage(mass fraction)of CMK-MP-OPC composite cementitious material can significantly improve the unconfined compressive strength of saline soil,which increases with the maintenance age.Furthermore,the best effect is achieved when 2%CMK,6%MP,2%OPC are added.The content of cemented structures can be used as a comprehensive index to reflect the performance of saline soil,and it can establish a good linear correlation with the unconfined com-pressive strength and permeability coefficient,and the SEM test results show improved micro-structure,reduced defect rate and higher density of saline soil after the improvement.
关键词
煤系偏高岭土/盐渍土/抗压强度/固结结构物含量/微结构Key words
coal metakaolin/saline soil/compressive strength/content of consolidated struc-ture/microstructure引用本文复制引用
基金项目
山西省自然科学基金(202303021212359)
出版年
2024
NETL
NSTL
维普
万方数据