锦屏一级水电站左岸浅表大理岩的卸荷微裂隙特征

发布时间：2018-04-02 10:53

  本文选题：卸荷　切入点：微破碎带　出处：《工程地质学报》2017年05期

【摘要】：在高山峡谷区,浅层岩体的表生改造相当发育。在锦屏一级水电站坝区陡峭的岸坡浅表大理岩岩体中采集定向标本,制作定向薄片,利用偏光显微镜统计和分析了微破碎带及带中微裂隙的方向分布情况。结果表明,(1)垂直于最小主应力σ_3的薄片中微破碎带在整体上未见明显定向性,垂直于最大主应力σ_1或中间主应力σ_2的薄片中微破碎带在整体上存在明显定向性,基本与岸坡平行;(2)微裂隙往往沿低指数晶面(包括解理面)发生,故晶内裂隙表现出直线式或台阶状样式,这符合最小能量原理;(3)卸荷应力场诱导控制微观卸荷裂隙的方向并使之具有强定向性。
[Abstract]:In the alpine canyon area, the supergene transformation of the shallow rock mass is quite developed. Directional specimens are collected from the shallow marble rock mass on the steep bank slope in the dam area of Jinping 1 Hydropower Station, and directional thin pieces are made. The distribution of microfracture zone and microfracture in microfracture zone is statistically analyzed by means of polarizing microscope. The results show that the microfracture zone perpendicular to the minimum principal stress 蟽 3 has no obvious orientation on the whole. The microfracture zone in the thin slice perpendicular to the maximum principal stress 蟽 1 or intermediate principal stress 蟽 2 has a clear orientation on the whole and is basically parallel to the bank slope. The microfractures often occur along the low exponential crystal plane (including the cleavage plane). Therefore, the intergranular fracture shows a linear or step pattern, which accords with the principle of minimum energy, and the direction of the micro-unloading fracture is controlled by the induced stress field of the unloading stress field and the direction of the micro-unloading fracture is strongly oriented.
【作者单位】： 南华大学核资源工程学院;山东科技大学山东省沉积成矿作用与沉积矿产重点实验室;中国科学院地质与地球物理研究所;绍兴文理学院;
【基金】：国家自然科学基金重点项目(41030749) 湖南省教育厅项目(2015SJY25) 山东省沉积成矿作用与沉积矿产重点实验室开放课题(DMSM201401)资助
【分类号】：TV223
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本文编号：1700059