岩土力学2024，Vol.45Issue(5)：1297-1308,12.DOI:10.16285/j.rsm.2023.0913
高温作用下非饱和黄土裂隙演化及其定量分析
Fracture evolution of unsaturated loess under high temperature and its quantitative analysis
摘要
Abstract
The hot-drying method for strengthening slope of foundation pit in loess holds potential application value,and the scientific evaluation of high-temperature loess crack evolution is a key link to verify the feasibility of the hot-dry method for strengthening loess.In this paper,a self-made experimental device was used to conduct crack evolution experiments on unsaturated loess samples with different initial dry densities and initial water contents at different high temperatures,and the changes in water content and surface crack of the soil samples were observed.Cracking indicators such as crack rate r,total crack length L,fractal dimension D,and average crack width W were quantitatively analyzed through experimental image processing.The analysis results show that r,L,and D all increase as the high temperature level increases,while W does not change significantly;the increase of initial dry density significantly reduces r,L,and D and significantly increases W;the increase of initial water content significantly increases r,L,D,and W.High temperatures significantly altered the crack initiation pattern of the soils,and the initiation cracks of the soils appeared rapidly under the 100 ℃ critical temperature.This may be related to the inhomogeneous extrusion of high-pressure water vapor.The high temperature greatly accelerated the fracture evolution process,but after exceeding 100 ℃,the acceleration of the fracture evolution was not significant.The mechanical mechanism of loess cracking and extension under high temperature is analyzed from the perspective of fracture mechanics,revealing the mechanism of high-temperature loess crack evolution.Considering the significant influence of matrix suction on crack evolution,a formula considering high temperature and matrix suction is established,highlighting the significant influence of high temperature on matrix suction to a certain extent.关键词
黄土/裂隙演化/高温/初始含水率/初始干密度Key words
loess/fracture evolution/high temperature/initial water content/initial dry density分类
土木建筑引用本文复制引用
赵再昆,王铁行,张亮,金鑫,鲁洁,阮嘉斌,邢昱..高温作用下非饱和黄土裂隙演化及其定量分析[J].岩土力学,2024,45(5):1297-1308,12.基金项目
陕西省自然科学基础研究重点项目(No.2020ZJ-49).This work was supported by the Key Science and Technology Program of Shaanxi Province(2020ZJ-49). （No.2020ZJ-49）
