岩土力学2026，Vol.47Issue(8)：2581-2597,17.DOI:10.16285/j.rsm.2025.0803
水-热循环作用下红层软岩裂隙扩展演化特征
Evolution characteristics of fracture propagation in red-bed soft rock under hydro-thermal cycling
摘要
Abstract
The combined effect of high temperature and alternating rain and heat significantly accelerates the disintegration and degradation of red-bed soft rocks,frequently triggering geological disasters such as slope cracking and deformation,collapse and landslide,as well as water and mud inrushes.This poses a severe challenge to the disaster prevention system in red-bed areas.Investigating the evolution patterns of rock fractures under hydro-thermal cycles plays a pivotal role in preventing and controlling disasters in red-bed regions.To quantitatively analyze the propagation of red-bed soft rock fractures under hydro-thermal cycles,digital image processing technology was adopted alongside a fracture aperture calculation method based on axial transformation.The evolution patterns of fracture apertures and the morphological changes in contour lines of red-layer soft rock fractures were systematically analyzed across a temperature range from room temperature to 100℃were systematically analyzed.The results show:(1)Under hydro-thermal cycle action,red-bed soft rock fractures exhibit significant expansion and evolution characteristics,and the increase in temperature significantly intensifies the fracture expansion effect.At 100℃,the fracture apertures increases by 1.96 to 10.54 times compared to the initial value,markedly higher than the 2.25 to 7.93 times observed at room temperature.Further research reveals that fractures with smaller initial apertures are more sensitive to hydro-thermal cycles,and this sensitivity becomes more pronounced with increasing temperature.(2)Spatially and temporally,the analysis of fractures aperture evolution reveals that aperture differences between adjacent measurement points increase significantly with cycling,indicating non-uniform fractures propagation.Higher temperatures significantly promote soft rock crack propagation.(3)The sand and gravel debris at fracture edges,being highly resistant to hydrothermal erosion,develops pronounced resistance differences compared to surrounding clay minerals undergoing continuous erosion.This leads to progressively larger aperture differences between adjacent points.Once clay matrix erosion reaches a critical level,the debris undergoes structural detachment.Synchronous observations reveal that despite local fluctuations in fracture contour roughness,it exhibits an overall significant decline during cycling,indicating sustained abrasion of fracture walls due to hydro-thermal coupling.(4)Hydrothermal cycles exacerbate soft rock damage through the combined effects of thermal expansion/contraction stresses and pore water phase transitions.Temperature variations promote microcrack propagation and enhance permeability while inducing capillary tension via evaporation-condensation cycles.Repeated hydration-dehydration cycles in clay minerals further induce tensile fracturing,resulting in significantly amplified cumulative damage.关键词
红层软岩/裂隙扩展/水-热循环/张开度/轮廓线/分形维数Key words
red-bed soft rock/crack propagation/hydro-thermal cycle/aperture/contour line/fractal dimension分类
矿业与冶金引用本文复制引用
钟庆云,黄震,吴云,林键,潘锐,古启雄,张小军..水-热循环作用下红层软岩裂隙扩展演化特征[J].岩土力学,2026,47(8):2581-2597,17.基金项目
江西省自然科学基金重点项目(No.2024BAB26047) （No.2024BAB26047）
国家自然科学基金(No.52274082) （No.52274082）
江西省重点研发计划青年科学家项目(No.20243BBI91032) （No.20243BBI91032）
江西理工大学清江青年拔尖人才支持计划(No.JXUSTQJBJ2020003).This work was supported by the Key Program of Natural Science Foundation of Jiangxi Province(2024BAB26047),the National Natural Science Foundation of China(52274082),the Jiangxi Province Key R&D Program for Young Scientists Project(20243BBI91032)and the Qingjiang Young Top-Notch Talents Support Program of Jiangxi University of Science and Technology(JXUSTQJBJ2020003). （No.JXUSTQJBJ2020003）
