高校地质学报2023，Vol.29Issue(6)：894-901,8.DOI:10.16108/j.issn1006-7493.2022056
化学老化生物炭对土体膨胀性和压缩性的影响及其机制
Effects of Chemically Aged Biochar on Soil Swelling and Compression Characteristics and Its Mechanism
摘要
Abstract
In recent years,biochar has been widely applied as a green and environmentally friendly soil modification material.After the addition to the soil,the physicochemical properties of biochar would be changed by the chemical environment of the soil,thus affecting the volume deformation characteristics of the modified soil.In order to explore the effects of chemically aged biochar on the swelling and compression characteristics of expansive soil,woody biochar was soaking into citric acid solution to simulate the chemical oxidation by plant organic acids,and its mechanism was explained by microstructural analysis(Scanning electron microscopy and Fourier transform infrared spectroscopy).The results show that:(1)The effect of aged biochar on soil swelling behavior is closely related to its particle size and dosage.When the particle size of biochar was fine(<0.25 mm),the enhanced promotion effect of aged biochar on the swelling of expansive soil was only observed in the presence of more biochar;while the enhanced promotion effect was occurred at low dosage with the increase of biochar particle size(0.25-1 mm);(2)The compressibility of biochar amended expansive soil is independent of the chemical aging of biochar,but related to the biochar dosage and particle size.Biochar could reduce the compressibility of expansive soil significantly,and this reduction becomes more pronounced with increasing biochar dosage and decreasing particle size;(3)Chemical aging affects the hydrophilicity of the expansive soil by changing the specific surface area and number of functional groups of biochar,thus the changed swelling properties of the soil;by contrast,the compressibility of the soil is more sensitive to changes in pore structure.关键词
生物炭/化学老化/膨胀土/膨胀性/压缩性Key words
biochar/chemical aging/expansive soil/swelling behavior/compression behavior分类
天文与地球科学引用本文复制引用
殷悦,顾凯,卢宇,沈征涛,施斌..化学老化生物炭对土体膨胀性和压缩性的影响及其机制[J].高校地质学报,2023,29(6):894-901,8.基金项目
国家重点研发计划课题子课题(2020YFC1808004 （）
2019YFC1509901) （）
国家自然科学基金面上项目(41977217)和陕西省重点研发计划子课题(2020ZDLSF06-03)联合资助 （41977217）
