地应力测量精度及其全要素量化表征研究

Geostress Measurement Accuracy and Its Extensive Quantitative Characterization

针对行业现状对地应力测量精度定义及其全要素量化表征方法进行了研究。概述了地应力测量方法、常用试验技术及其测量精度方面存在的问题与原因。从闭环测量角度给出了地应力测量及其精度的定义,在对测量精度研究分类和总结的基础上,提出了地应力测量精度表征体系的构成和分层,指出了测量精度研究的意义、测量方法与测量技术的定义及其测量精度问题。阐述了地应力测量精度全要素量化表征的思路和含义、三维物理模型测量精度试验装置、坐标设定和表征程序,给出了平均方式和最大值方式的表征指标,以及二维和三维测量的精度表征公式,对角度误差的计算方法进行了讨论,对表征方式与技术研发要求的对应关系进行了说明。以早期的USBM孔径变形计和CSIRO空心包体应变计物理模型试验结果的测量精度表征为例,展示了测量精度的量化表征过程,与原有测量精度表征指标进行了对比,获得上述试验技术最大值方式单一指标的总体测量误差分别为10%和27%。首次获得了两试验方法的全要素测量精度数据,比较显示前者的总体测量精度大大优于后者。

In this paper we studied the definition and extensive characterization of geostress measurement accuracy in view of the present situation of the research field.First of all,we reviewed the geostress measurement methods,commonly used techniques,and the problems in measurement accuracy as well as their causes.From the perspective of closed-loop measurement,we gave our definitions of geostress measurement and geostress measurement accuracy.On the basis of classifying and summarizing historic researches,we presented the composition and structure of a characterization system for geostress measurement accuracy,expounded the significance of accuracy research,the difference between measurement method and measurement technology,as well as the accuracy problems.Furthermore,we presented the idea and connotations of quantitatively characterizing all factors of geostress measurement accuracy and gave the 3D physical model test device for measurement accuracy and its coordinate setting and characterization program.We also introduced the characterization formulae of all factors which include indexes of average-mode and maximum-mode in 2D and 3D measurement.In addition,we discussed the method of calculating angle error and explained the relationship between characterization modes and technical requirements.Taking the example of characterizing the measurement accuracy of the physical model test results of USBM borehole deformation gauge and CSIRO hollow inclusion strain gauge,we demonstrated the process of our extensive quantitative characterization.By comparing the characterization indexes with the original ones,we found that the overall measurement error of the single index of the maximum-mode of USBM and CSIRO is 10%and 27%,respectively.By using the present extensive characterizing method in consideration of all factors,we found that the measurement accuracy of USBM is superior to that of CSIRO.