硅酸盐通报2024，Vol.43Issue(11)：4167-4176,10.
石灰-沸石粉改良膨胀土强度特性及微观机理研究
Strength Characteristics and Microscopic Mechanism of Expansive Soil Improved by Lime-Zeolite Powder
摘要
Abstract
Aiming at the engineering disease problems caused by expansion and contraction of expansive soil and the pollution problems caused by lime improved expansive soil,this paper taked the expansive soil in Nanyang area of Henan province as the object of study,and prepared the specimens of vegetal expansive soil and improved soil with different dosages of lime and zeolite powder.The unconfined compressive test,free expansion rate test,triaxial test,X-ray diffraction(XRD)analysis and scanning electron microscope(SEM)test were carried out to study the strength characteristics and microscopic reinforcement mechanism of the lime-zeolite powder composite improved expansive soil.The results indicate that lime improvement and lime-zeolite powder composite improvement can effectively improve the strength of soil and reduce the free expansion rate,and the composite improvement effect is better.The optimum content of lime and zeolite powder is 6%(mass fraction)and 12%(mass fraction),respectively.The stress-strain curves of lime improved soil and composite improved soil are transformed into the strain-softening type.The addition of lime significantly improves the cohesion of the expansive soil.With the increase of zeolite powder content,the triaxial shear strength of composite improved soil increases continuously,and the internal friction angle increases first and then decreases.Zeolite powder reacts with lime to form a large amount of cementitious material,which fills the pores with soil and makes the microstructure more dense,increases the frictional resistance between soil particles,and increases the strength of the soil at the macro-level.关键词
膨胀土/沸石粉/石灰/强度特性/无侧限抗压试验/三轴试验/微观机理Key words
expansive soil/zeolite powder/lime/strength characteristic/unconfined compressive test/triaxial test/microscopic mechanism分类
建筑与水利引用本文复制引用
张玉国,赵春豪,张兆彬,张自来..石灰-沸石粉改良膨胀土强度特性及微观机理研究[J].硅酸盐通报,2024,43(11):4167-4176,10.基金项目
国家自然科学基金(U1204511) （U1204511）
河南省自然科学基金(222300420596) （222300420596）
河南省高等学校重点科研项目(19A560027) （19A560027）
