中国地质灾害与防治学报2025，Vol.36Issue(2)：145-151,7.DOI:10.16031/j.cnki.issn.1003-8035.202310030
水泥聚丙烯纤维加固黏性土的浸水软化时效特性
Softening aging characteristics of clayey soil reinforced with cement and polypropylene fibers under water immersion
摘要
Abstract
In this paper,the mechanical properties of silty clay reinforced with cement and polypropylene fibers were studied through direct shear tests.Additionally,water immersion softening tests were conducted to simulate the effects of long-term rainfall on the strength of both plain and reinforced soils,revealing the mechanical behaviour and microstructural changes of the samples after softening.The results indicate that the cohesion and internal friction angle of the reinforced soil increase with higher cement and fiber content,but the rate of increase diminishes behind a certain threshold.Based on these findings,the optimal reinforcement composition is determined to be 6％cement and 0.4％polypropylene fibers.Water immersion softening tests conducted on samples with this composition reveal the following characteristics:In the initial stage of water immersion,due to the hydration and hydrolysis reaction,the cementation between soil particles is enhanced,and the close bonding between soil and fibers further increases the cohesion of the soil.Energy exchange between soil and water ions in the soil reduces the thickness of the water film bound to clay particles,slightly increasing the internal friction angle;as the immersion time increases,the accumulation of free water leads to relative movement and dispersion of soil particles into blocks.However,the strong cementation provided by hydration products and the encapsulating effect of fibers maintain the soil's structural integrity,resulting in a gradual decrease in cohesion and internal friction angle.These findings provide critical mechanical parameters and theoretical insights for the application of cement and polypropylene fiber reinforcement in cohesive soils.关键词
粉质黏土/水泥聚丙烯纤维土/抗剪强度/浸水软化/时效特征Key words
silty clay/cement-polypropylene fiber soil/shear strength/water immersion softening/aging characteristics分类
天文与地球科学引用本文复制引用
亓星,刘焕,杨浪,曹汝亮..水泥聚丙烯纤维加固黏性土的浸水软化时效特性[J].中国地质灾害与防治学报,2025,36(2):145-151,7.基金项目
地质灾害防治与地质环境保护国家重点实验室开放基金项目(SKLGP2022K008) （SKLGP2022K008）
