金川龙首矿西二采地应力状态分析

In-situ Stress State Analysis in the Secondary West Mining Area of Jinchuan Longshou Mine

为保证龙首矿西二采区开采和支护工程的顺利实施,在龙首矿西二采区1 430 m、1 514 m、1 610 m3个中段巷道上,采用空心包体应力解除法进行地应力测量,共获得6个测点三维应力测量数据,同时绘制各个测点不同法线方向的截面应力椭圆。结果表明:在井下100～280 m深度范围内,最大主应力量值约为10～14 MPa,属于中等应力水平;测点2、5、6最大主应力量值与最小主应力量值差值较大,范围在8.2～11.2 MPa;地应力状态特征参数KHh、KHV、Kav分布范围分别为1.43～4.81、1.06～3.1、0.88～2.28,基本在先前的参数研究范围内;各测点最大水平主应力大于垂直应力,构造力处于主导地位,但从各测点主应力与水平面的夹角大小可知,非水平应力场特征开始出现,显示该区应力特征的复杂性;最大主应力的方向为NNE、NWW2组,优势方向为NNE向,至于NWW方向是否可能成为西二采区新的最大主应力的优势方向还需进一步进行地应力测量工作方可得出结论。

In order to guarantee the smooth construction of the mining and supporting engineering in the secondary west mining area of Jinchuan Longshou Mine, an hollow inclusion stress relief method was adopted to obtain three dimensional stress data of 6 measuring points at the three horizontal roadways of 1 430 m, 1 514 m, and 1 610 m, and the section stress-ellipses at different normal directions of each site was drawn. The results showed that the maximum principal stress value is about 10~14 MPa in the depth range of 100-280 m underground, and it belongs to the medium stress level;The difference between the maximum and the minimum principal stress values in the measuring points of 2, 5, and 6 are relatively large, within the range of about 8.2~11.2 MPa;The KHh, KHV, and Kav of stress characteristic parameters are distributed within ranges of 1.43~4.81, 1.06~3.1, 0.88~2.28, respectively, and these are basically within the previous scopes;The maximum horizontal principal stress at each measuring point is higher than the vertical stress, and the tectonic stress is dominant in this region. However, according to the angle between the principal stress and the horizontal plane, it can be seen that the characteristics of the non-horizontal stress field begin to appear, indicating the in-situ stress in this area are complex;The directions of the maximum principal stress include two groups: NNE, the dominant direction, and NWW, of which the possibility in becoming the dominant direction of the new maximum principal stress, needs further in-situ stress measurement.