套筒致裂法测试地应力的原理与方法

Principle and method of sleeve fracturing method in testing in-situ stress

为更加精准地获得煤矿井下地应力的大小和方位,提出了一种测试地应力的新方法。该方法采用具有高频自动存储测试压力并生成压力-时间曲线功能的JHDC-1型地应力测试仪,通过对某个测试孔实施2次加压致裂,能够获得精确的油压值及相应的致裂方程。采用弹性力学中的圆孔应力集中理论,详细地剖析了油压值与致裂压力之间的换算关系,给出了三孔致裂法测试地应力的基本原理。并详细的阐述现场测试方法与步骤。该测试方法适用于各种地质条件和井下环境的测试,尤其适合煤矿井下地应力测试的现场使用。

In order to more accurately obtain the coal mine ground stress level and orientation,authors proposed a new method for testing ground stress. The type JHDC-1 stress testing instrument is adopted and can automatically store testing pressure with high frequency and generate the test pressure-time curve. Through the implementation of two pressurized fracturing on a test hole, it can get accurate oil pressure value and its corresponding fracturing equation. Authors adopted the elastic stress concentration theory of round hole, analyzed the conversion relationship between the oil pressure value and its fracturing pressure, and provided the basic principle of three hole crack method for testing ground stress. In addition, authors also gave a detailed description for field test methods and steps. The test method is applicable to various geological conditions and underground environment test, especially suitable for on-site coal mine ground stress test.