The Characteristics of Geostress and Its Geological Engineering Significance of Underground Water-sealed Cavern

The geostress characteristics of one underground water-sealed cavern was investigated based on geostress data collected by hydraulic fracturing, and the axis direction of the cavern was testified by numerical simulation results. The results shows that: (1) the direction of regional maximum principal stress is NWW, and the regional maximum principal stress shows a tendency deflecting to the east as the depth increases; (2) the current stress field is one of the typical tectonic stress field, which is dominated by reverse fault stress mechanism; (3) both maximum and minimum horizontal principal stress show a linear rise with depth; (4) the coefficient of horizontal pressure lies within the envelope line of Chinese Mainland, showing the trait of dispersion in the shallow and convergence in the deep; (5) with the maximum horizontal principal stress being the maximum principal stress and the vertical principal stress being the minimum principal stress, the minimum horizontal principal stress is the intermediate principal stress; (6) the axis direction of the cavern is recommended as N55°W considering the influence of the maximum horizontal principal stress and preferred structural plane.