期刊论文

CHARACTERISTICS OF UNLOADING MICRO CRACKS IN SHALLOW ROCK MASS AT LEFT BANK OF JINPINGⅠHYDROPOWER STATION DAM

中文

工程地质学报

1004-9665

2017

25

5

1381-1388

10.13544/j.cnki.jeg.2017.05.027

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

本校为第一机构

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 σ3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σ1或中间主应力σ2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。

In the mountain valley area,epigenetic deformation of the shallow rock mass is common. Directional samples are taken at left bank of Jinping Ⅰ hydropower station dam. Thin sections are made. Direction distribution of micro fracture zones and micro cracks are analyzed by polarization microscope. Three conclusions are drawn.Firstly,micro fracture zone in thin section which is perpendicular to σ_3 has no obvious directionality,but micro fracture zone in thin section which is perpendicular to σ_2 or σ_1 is parallel to bank surface. Secondly,mic...