论文部分内容阅读
在北京市房山区迎风坡花岗闪长岩３００ｍ深钻孔中，采用以水泥端帽法为主的岩心定向技术，并在钻进和取心过程中采取特殊措施，在钻孔中距地表２５ｍ～３０１ｍ整个深度段内取得了直径８６ｍｍ的定向岩心。对深度２９４ｍ的定向岩心进行了声发射Ｋａｉｓｅｒ效应试验。岩石试件为圆柱形，直径３０ｍｍ，高度７５ｍｍ。在垂直方向，利用声发射Ｋａｉｓｅｒ效应估计的垂直主应力为７．７ＭＰａ；在２９４ｍ岩体静岩压力为７．９ＭＰａ；两者基本相同。在水平面内，对４个方向的试件进行声发射Ｋａｉｓｅｒ效应试验，得到相应的各个方向的压应力，由此估算的水平最大和最小主应力分别为２１．２ＭＰａ和１２．１ＭＰａ。水平面内最大主应力的方向基本为ＳＮ方向。将声发射Ｋａｉｓｅｒ效应测量结果与水压致裂法的测量结果进行对比，二者具有很好的一致性。
In the 300m deep boreholes of the Yingfengpo granodiorite, Fangshan District, Beijing, the core-oriented technique with cement-cap method is adopted and special measures are taken during drilling and coring. Directional cores with a diameter of 86 mm were obtained from 25 m to 301 m throughout the depth. Acoustic emission Kaiser effect test was carried out on the directional core with a depth of 294m. Rock specimens cylindrical, diameter 30mm, height 75mm. In the vertical direction, the vertical principal stress estimated by the Kaiser effect of acoustic emission is 7.7 MPa; the rock pressure at 294 m is 7.9 MPa; and the two are basically the same. In the horizontal plane, the Kaiser effect test was carried out on the specimens in four directions to obtain the corresponding compressive stress in all directions, and the maximum and minimum principal stresses estimated by this method were 21.2 MPa and 12.1 MPa, respectively. The direction of the maximum principal stress in the horizontal plane is basically the SN direction. The results of Kaiser effect of acoustic emission and the results of hydraulic fracturing are compared, the two have good consistency.