循环载荷下干燥及饱和砂岩的变形及声发射特征

发布时间：2018-03-30 14:23

本文选题：单轴压缩　切入点：循环加卸载　出处：《东北大学学报(自然科学版)》2016年08期

【摘要】：对取自陕西榆横矿区小纪汗煤矿顶板砂岩的干燥和饱和试件进行单轴循环加卸载试验及声发射监测,分析了不同含水状态岩石的强度以及变形特征、声发射特征和加卸载响应比变化情况.结果表明,水对上述性质具有显著影响:饱和试件强度和滞回环数量均低于干燥试件,压密阶段轴向应变比干燥试件增加18.9%,峰值强度前轴向应变比干燥试件降低17.4%,干燥和饱和试件在循环加载过程中弹性模量均有增大趋势;干燥试件在整个加卸载过程中声发射能量累积为3.87×10-11J,饱和试件声发射能量累积为2.58×10-11J,仅为干燥试件的66.67%;干燥和饱和试件的加卸载响应比呈现类似的变化规律,但饱和试件的加卸载响应比峰值特征时间比干燥试件短,宏观裂纹形成得更早.
[Abstract]:Uniaxial cyclic loading and unloading tests and acoustic emission monitoring were carried out on the dry and saturated specimens of roof sandstone taken from Xiaojihan coal mine in Yuheng mining area, Shaanxi Province. The strength and deformation characteristics of rocks with different water-bearing states were analyzed. The results show that water has a significant effect on the above properties: the strength and the number of hysteresis loops of saturated specimens are lower than those of dry specimens. The axial strain is 18.9m higher than that of the dry specimen at the compaction stage, and the peak strength of the former axial strain is 17.4 less than that of the dry specimen. The elastic modulus of the dry and saturated specimens increases during cyclic loading. During the whole loading and unloading process, the accumulation of acoustic emission energy was 3.87 脳 10 ~ (-11) J for the dry specimen and 2.58 脳 10 ~ (-11) J for the saturated specimen, which was only 66.67 of the dry specimen, and the loading and unloading response ratio of the dry and saturated specimen showed a similar change. However, the loading and unloading response time of saturated specimen is shorter than that of dry specimen, and the macroscopic crack is formed earlier.
【作者单位】：东北大学资源与土木工程学院;贵州省非金属矿产资源综合利用重点实验室;贵州大学矿业学院;
【基金】：国家重点基础研究发展计划项目(2013CB227902) 国家自然科学基金资助项目(51404067)
【分类号】：TD31

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