摘要
差应变分析法是一种理论基础可靠的常用地应力测量方法,然而受测试条件限制以及测试技术难度等因素的影响,目前该方法的实际应用受到了一定限制。针对这一现状,在差应变分析法的理论基础上,以古地磁岩心定向技术为基础,引入岩石波速各向异性分布特征与地应力方向的相关原理,提出了一套简易可行的室内地应力测量新方法,即:主方向差应变分析法。该方法根据岩石波速分布特征确定出水平主应力的方向,依据水平主应力方向来制备差应变实验岩样并进行实验。和常规差应变分析法测量结果相比,该方法测量所得地应力大小的相对误差一般小于3%,地应力方向的误差一般小于5°。实例研究表明,该方法降低了实验技术难度,测量精度满足工程技术要求,具有推广价值。
Theoretically, the Differential Strain Analysis （DSA） method based on solid theory is widely used in in - situ stress measurement, but the application of the method is restricted by the rigorous and complicated experimental conditions and test procedures. In view of the present situation, based on the DSA method and the technique of palaeomagnetism orientation, the theory about the wave velocity anisotropy and the orientation of stress is introduced to the DSA test, a new method named the principal direction DSA method is developed to make the laboratory test simple and feasible. According to the distribution characteristics of the rock wave velocity, the method is used to determine the orientation of the principal stress horizontally, based on which DSA core samples are prepared for the test. Compare with the conventional DSA method, the relative error of the magnitude of in - situ stress using the new one is less than 3%, and the error of the orientation of in - situ stress is less than 50. The case study indicates that the method decreases the technical difficulty of test dramatically, and its accuracy meets the requirement of engineering technologies, so it deserves to be popularized.
出处
《石油钻采工艺》
CAS
CSCD
北大核心
2008年第2期61-64,共4页
Oil Drilling & Production Technology
关键词
地应力测量
波速各向异性
差应变分析法
主方向
stress measurement
wave velocity anisotropy
DSA method
principal direction
