岩体结构面产状测量的钻孔摄像技术及其可靠性

针对钻孔摄像技术对结构面产状测量只限于垂直孔的现状，以钻孔孔口圆心为原点，建立空间左手直角坐标系，对倾斜孔中结构面产状的确定方法进行了详尽的阐述和推导，得出了精确的解析计算公式，并基于C#语言进行编程，开发了IDOIB软件，通过测试表明此方法及其程序的正确性.采用PVC管模拟钻孔孔壁，进行钻孔摄像技术用于结构面产状测量的可靠性试验研究，结果表明:(1)对于垂直孔，测量结果的倾向绝对误差为-3°，4°]、倾角绝对误差为-1.5°，1.0°]，说明该技术用于垂直孔进行结构面产状测量是可靠的，能满足工程应用精度.(2)当PVC管的倾伏向为270°、倾伏角为25°时，结构面产状可靠度为0.10；倾伏向为176°、倾伏角为60°时，结构面产状可靠度为0.67.PVC管倾伏角的不同导致结构面产状可靠度的差异.(3)一般岩体工程的结构面产状测量结果应具有高等级可靠度(不小于0.8)，即须在倾伏角不小于71°的钻孔内采用该技术进行测量. 

Calculation Methods of Rock Mass Discontinuity Orientation Measured by Borehole Camera Technology and Technology Reliability

For the issue that borehole camera technology only is applied to the vertical borehole currently, the calculation process for discontinuity orientation in inclined borehole is presented in this paper. With the circle centre of drill orifice as the origin, the left-handed Cartesian coordinate system is constructed and the precise analytic formulas for discontinuity orientation in inclined borehole are obtained. On this basis, the IDOIB software is developed using C# programming language. The validity of analytic formulas and program are verified by the principle of borehole camera technology. In addition, the PVC pipe experiments are conducted to examine the reliability of borehole camera technology for measurement of discontinuity orientation. Results show that: (1) For vertical holes, absolute errors of dip directions range from -3° to 4°, and those of dips range from -1.5° to 1.0°. The technology is reliable for measurement of discontinuity orientation in vertical boreholes, and it can satisfy the needs of rock engineering. (2) For inclined PVC pipes with trend of 270° and plunge of 25°, the reliability degree of discontinuity orientation is 0.10; while inclined PVC pipes with trend of 176° and plunge of 60°, the reliability degree of discontinuity orientation is 0.67. The difference of pipe plunge results in the reliability difference of discontinuity orientation. (3) The reliability of discontinuity orientation should be high (the reliability degree is no less than 0.8) for general rock engineering, so the plunge of inclined borehole should be no less than 71°.