排灌机械工程学报2024，Vol.42Issue(8)：818-825,850,9.DOI:10.3969/j.issn.1674-8530.23.0182
碱激发煤矸石粉对砒砂岩水泥复合土强度影响的试验研究
Experimental study on effect of alkali-activated gangue powder on strength of Pisha sandstone cement composite soil
摘要
Abstract
In order to reduce the serious soil erosion in the Pisha sandstone area,promote the effective utilization of loose Pisha sandstone,as well as improve the utilization rate of waste coal gangue,by use of X-ray diffraction,scanning electron microscopy,thermogravimetry,and mercury pressure test methods,the mechanism of alkali excitation and gangue powder substitution rate on the mechanical strength of Pisha sandstone-cement composite soil from the microscopic level of the composition of the curing product,microscopic morphology,and the evolution of the pore structure was revealed.The re-sults show that the addition of alkali causes the dissolution of montmorillonite and coal gangue powder in Pisha sandstone,promotes the generation of N-A-S-H and C-A-S-H gel,which increases its strength.With the increase of gangue substitution and the relative reduction of cement dosage,the Ca content decreases,the C-A-S-H gel content decreases,and the N-A-S-H gel gradually transforms into non-cementitious Ca(Na)-lingite,resulting in a gradual decrease in its strength.When the alkali equivalent is 4％and the gangue substitution rate is 7％,the porosity of gangue powder-Pisha sand-stone cement composite soil is 29.20％,and the proportion of small pores is 46.48％.Moreover,the 7d strength can meet the requirement of 1.0-3.0 MPa for the sub-base of secondary and sub-secondary highways.This study can provide a theoretical basis for the application of gangue powder-Pisha sand-stone cement composite soil in road paving and channel lining.关键词
砒砂岩/复合土/煤矸石粉/碱激发/微观机理Key words
Pisha sandstone/composite soil/coal gangue powder/alkali-activated/microscopic mechanisms分类
建筑与水利引用本文复制引用
李大虎,李晓丽,王重阳,赵晓泽..碱激发煤矸石粉对砒砂岩水泥复合土强度影响的试验研究[J].排灌机械工程学报,2024,42(8):818-825,850,9.基金项目
国家自然科学基金资助项目(51869022) （51869022）
内蒙古自然科学基金资助项目(2020MS05051) （2020MS05051）
