三维地应力BWSRM测量新方法及其测井机器人在重大工程中的应用

地壳上层岩体的应力状态是地壳最重要的性质之一,获取岩体应力状态最直接、可靠的手段是原位地应力测量.首先简要回顾地应力测量的研究历程及其发展现状,分析岩石力学与工程中常用的几种地应力测量方法和技术.重点介绍钻孔局部壁面应力解除法(BWSRM)这一新的三维地应力测量方法的原理,以及基于BWSRM的地应力测井机器人研制过程和...

A NEW 3D IN-SITU ROCK STRESS MEASURING METHOD:BOREHOLE WALL STRESS RELIEF METHOD(BWSRM) AND DEVELOPMENT OF GEOSTRESS MEASURING INSTRUMENT BASED ON BWSRM AND ITS PRIMARY APPLICATIONS TO ENGINEERING

It is important to conduct a research on the stress state of the rock masses in the upper earth′s crust. In-situ rock stress measurement is the basic and reliable access to obtain the stress state of the rock masses. The development of in-situ rock stress measurement and state-of-art of research on it are overviewed. Then，several in- situ rock stress measuring methods and techniques are briefly analyzed in rock mechanics and engineering. A new method，borehole wall stress relief method(BWSRM) to determine the in-situ 3D rock stress tensor in a single drilled borehole is deliberated. An original geostress measuring instrument typed by BWSRM-H01 is designed and manufactured based on the principle of in-situ rock stress measurement with BWSRM. The in-situ test for rock stress with BWSRM is carried out at an experimental tunnel in Jinping II hydropower station，China，where the buried depth of overburden is about 2 430 m. It is shown that the two principal stress components close to the horizontal direction are the maximum and intermediate principal stress respectively；while the stress component close to vertical direction is just the minor principal stress in the testing site. The magnitudes of the maximum and the intermediate principal stress are high；and both of them are very close.