淮南矿区深部地应力场特征研究

利用水压致裂法和套孔应力解除法对淮南矿区-500～-1 000 m深度范围内的12个矿井进行了地应力测量，取得了19个有效测点的数据。数据分析表明：（1）淮南矿区深部地应力场以水平应力为主，构造应力占绝对优势，属于典型的构造应力场类型；（2）地应力量级属高应力水平；（3）垂直主应力、最大及最小水平主应力随深度的增加均呈增大趋势；（4）侧压系数 随深度增大而减小，地应力场有从大地动应力场型向准静水压力场型过渡的趋势；（5）侧压比 的回归曲线分布于Hoek-Brown内外包线带内，且变化趋势与Hoek-Brown曲线相似，但与Hoek-Brown曲线相比，回归曲线 值偏小；（6）最大水平主应力与最小水平主应力的比值范围为1.12～2.02，其中68.42%的测点分布在1.67～2.02之间；（7）最大水平主应力方位为NEE－EW向。最后探讨了淮南矿区地应力与地质构造的关系，分析认为，矿区最大主应力方向与构造运动密切相关，矿区现今构造应力场最大主应力方位与实测最大水平主应力方位大致吻合。

Characteristics of in-situ stress field for deep levels in Huainan coal mine

The in-situ stress measurements of 12 pits have been conducted within the depths of from-500 to-1 000 m in Huainan Coal Mine by using hydraulic fracturing technique and stress relief method by overcoring;and the measurement data of 19 effective measuring points have been obtained.The analyses of the measurement data indicate that:(1) The in-situ stress field in Huainan Coal Mine,in which the tectonic stress takes absolute predominance,is dominated by horizontal stress and belongs to typical tectonic stress field.(2) The magnitudes of the in-situ stresses are high stress level.(3) Vertical principal stress,maximum and minor horizontal principal stresses all show increasing trend with the increase of depth.(4) The ratio of maximum horizontal principal stress to vertical principal stress,,decreases with the increase of depth;the in-situ stress field has the changing tendency from dynamic to static.(5) The regression curve for the ratio of average horizontal principal stress to vertical principal stress,,distributes between the maximum and minimum envelopes of Hoek-Brown curve;and its change trend is similar with the Hoek-Brown curve,but compared with the Hoek-Brown’curve,the value of the regression curve is smaller.(6) The ratio of maximum to minimum horizontal principal stress ranges from 1.12 to 2.02,in which 68.42% of measuring points ranges from 1.67 to 2.02.(7) The orientation of maximum horizontal principal stress is about NEE-EW.At last,the relationship between in-situ stress and tectonics for Huainan mining area is discussed.The analysis suggests that the orientation of maximum principal stress is closely related with the tectonic movement,while the orientation of current tectonic stress field is roughly identical with that of the measured maximum horizontal principal stress of mining area.