用动态岩石电阻率变化各向异性探测岩石主破裂扩展方向

Despite the traditional method of geoelectric resistivity is used to detect the landslip and engineering geology hazards is time-honoured, it is merely used to detect the geological structure by the electric profiling and electric sounding and can not be used for long-term field monitoring in the landslip and engineering geology hazards because it easy disturbed by some unfavored factors, such as weather and other natural sources. .Avoiding the most complex and difficult thorny problem about the state and manner of stress in rock rupture from principle and directly makes the resistivity changing anisotropy due to rock rupture contact with the change in conductivity of interconnected pore and crack fluid inside the rock using the method of apparent resistivity changing anisotropy in this item. Accordingly can protrude the resistivity changing anisotropy in the unsubstantial or most stress places (these places sometimes are perdu，easy not be detect )of medium after medium is loaded and establish the quantitative relation between resistivity change anisotropy and the main fracture spread direction of rock . The method can not only protrudes the resistivity changing anisotropy but also eliminates the systematic disturbance to the measurements caused by some unfavorable factors, such as rainfall, inaccuracy of measuring equipment, etc in calculating. Therefore, the method can be used for long-term field monitoring and will be of practical significance monitor the dynamic process of medium changed from steady state to non-steady state. The method has further virtue that is the ability of detecting the electric property structure of medium before field monitoring, which can achieve the aim that an apparatus has multiple functions..Three-research jobs all had been accomplished in this item. 1, Indoor large model simulate experiment, with true triaxial pressure, shear, twisting and frictional slipping together four kinds of loading tests were accomplished init, which got the result that the dominant orientation of microcracks extending in the rock can be determined by the method of resistivity changing anisotropy. 2, Field fracturing of manual collapse experiment. The experiment was done thrice, which includes quadric cracking cannot be controlled tests and once cracking can be controlled test. The experimental results show that we can not only determine the dominant orientation of microcracks extending in the rock by the method of resistivity changing anisotropy, but also descry the strike changing of the microcracks extending process in medium from the results of resistivity changing anisotropy. At the same time, the rupture premonition of medium was observed. 3, The detection of the electric property structure of medium and field monitoring test of resistivity changing anisotropy for typical rock body of geologic hazard, which taken part in the《demonstrate and popularize in monitoring and forecast new technique for typical rock body of geologic hazard》item, had been continuanced for more than four months at Xia-kou, Ya-an city, Sichuan, China. The results of detection in electric property structure of medium verify formerly exploring borderline of creep deformation, depth and thickness of groundwater horizon, and the superstratum property in the landslip body. The results for method of apparent resistivity changing anisotropy obtain the slipping trend and changing speed in landslip body of measuring-point, and verify the method has the capability of eliminating the systematic disturbance to the measurements caused by some unfavorable factors and the influence of inveracious measuring value on calculating results...

动态岩石电阻率变化各向异性，直接反映岩石微裂隙的变化。它可以用来探测岩体(隐伏)裂隙的发生、发展和动态变化，预测裂隙发展的趋势，为灾害预警、预报提供可靠的前兆特征信息。本项目用构造变形模拟及现场观测实验，研究用岩体电阻率变化各向异性，探测岩体主破裂扩展方向和前兆特征的适应方法，及其在野外应用的条件和适用范围。