水利水电技术（中英文）2025，Vol.56Issue(2)：200-215,16.DOI:10.13928/j.cnki.wrahe.2025.02.017
含缺陷砂岩单轴压缩裂纹类型及演化规律试验研究
Experimental study on the types and evolution of uniaxial compression cracks in defective sandstone
摘要
Abstract
[Objective]The mechanical strength of the fractured rock body will be deteriorated under loading,which is easy to further trigger rock rupture and affect the rock engineering,and analyze the acoustic emission energy characteristics,the main frequency change and the RA-AF value distribution of the defective sandstone under uniaxial compression.[Methods]Based on the acoustic emission parameters,we investigate the fracture mechanism,crack type and evolution of sandstone,and combined with scanning electron microscopy,we investigate the connection between the fracture micro-morphological characteristics and the macro-fracture.[Results]The presence of defects has obvious deterioration effect on the mechanical strength of sandstone,the change of acoustic emission energy exists in four phases,namely,"fluctuation period,smooth period,violent fluctuation period,and upward surge period",and the acoustic emission parameter AF mainly distributes in the range of 0～500 kHz,and RA mainly distributes in the range of 0～2.0 ms·V-1,and the fracture surface of sandstone is divided into three types:tensile fracture,shear fracture,and composite fracture of tension-shear type.The sandstone fracture is divided into three types:tensile fracture,shear fracture,and tensile-shear composite fracture.[Conclusion](1)The strength of sandstone shows an overall increasing trend with the increase of fracture angle;(2)The crack evolution process can be divided into:initial wing tension crack-composite type crack(0°～45°)→ initial anti-wing tension crack-anti-wing crack(60°～75°)→ initial wing tension crack-secondary wing crack(90°);(3)The main frequency signal accounts for 71％～96％of the low-frequency,and the high-frequency accounts for 3％～23％,and the damage process mainly produces large-scale cracks;(4)the proportion of tension cracks is more than 70％,the proportion of shear cracks fluctuates around 20％,and the tension damage is dominant;(5)the fracture of the rupture surface of the sandstone is dominated by transgranular fracture(TG)and accompanied by along-granular fracture(IG),and the intact sandstone is mainly transgranular tensile-type fracture,and defective sandstone is mainly transgranular tension-shear composite-type fracture The macroscopic crack fracture forms of sandstones and the microscopic morphologic features have a corresponding relationship.关键词
单轴压缩/声发射/裂纹类型/演化规律/扫描电镜/影响因素/力学性能/砂岩Key words
uniaxial compression/acoustic emission/fracture mechanism/crack evolution/scanning electron microscope/influencing factors/mechanicalproperties/sand stone分类
资源环境引用本文复制引用
吴迪,江兴元,赵珍贤,田俊伟,王福林..含缺陷砂岩单轴压缩裂纹类型及演化规律试验研究[J].水利水电技术（中英文）,2025,56(2):200-215,16.基金项目
国家自然科学基金项目(42007271) （42007271）
贵州省科技支撑计划项目(黔科合支撑[2023]一般119) （黔科合支撑[2023]一般119）
