为了解决裂隙较发育岩体在常规地应力测试方法下难度较大、成功率较低的问题,分析研究了各种地应力测试方法在裂隙较发育岩体中的适用性。结果表明:钻孔孔底应变解除法可用于节理裂隙较为发育岩体的地应力测量,并在某水电站坝基柱状节理岩体中得到应用;采用该方法成功获得某水电站坝基柱状节理岩体的平面应力状态,并对3个不同方位的钻孔测试获得三维应力状态;通过坐标转换至各个钻孔坐标系下的应力结果与单孔孔底应力测试结果较为接近,不同方法的测试结果得到互相验证。故钻孔孔底应变解除法能较好地适用于诸如柱状节理等裂隙较发育岩体的地应力测量与研究之中,可供类似工程参考使用。
Abstract
In order to address the difficulty and low success rate of conventional stress detection methods applied to jointed and fractured rock mass, we found that the method of strain relieving in the bottom of borehole is applicable and we employed this method to the columnar jointed rock mass of the dam foundation of a hydropower station. Through this method, we obtained the plane stress of the jointed rock mass and the three-dimensional stress state from three boreholes in different directions. The stress results transformed to the borehole coordinate system were close to the test results of single borehole stress, verifying the calculation results. In conclusion, the method of strain relieving in the bottom of borehole could be well applied to the stress measurement of fractured rock mass such as columnar joints.
关键词
水电站 /
节理岩体 /
地应力 /
孔底应变解除法 /
三维应力状态
Key words
hydropower station /
jointed rock mass /
in-situ stress /
borehole bottom strain relieving method /
three-dimensional stress state
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] LJUNGGREN C, CHANG Yan-ting, JANSON T, et al. An Overview of Rock Stress Measurement Methods[J]. International Journal of Rock Mechanics and Mining Sciences, 2003, 40(7/8): 975-989.[2] CHANG Soo-ho, LEE Chung-in, LEE Youn-kyou. An Experimental Damage Model and Its Application to the Evaluation of the Excavation Damage Zone[J]. Rock Mechanics and Rock Engineering, 2007, 40(3): 245-285.[3] MAEJIMA T, MORIOKA H, MORI T.Evaluation of Loosened Zones on Excavation of a Large Underground Rock Cavern and Application of Observational Construction Techniques[J].Tunnelling and Underground Space Technology,2003,18 (2/3):223-232.[4] FAIRHURST C. Method of Determining “In situ” Stresses at Great Depth[R]. Omaha: Missouri River Division, U.S. Corps of Engineers, 1968. [5] HUDSON J A, CORNET F H, CHRISTIANSSON R. ISRM Suggested Methods for Rock Stress Estimation-Part Ⅰ: Strategy for Rock Stress Estimation[J]. International Journal of Rock Mechanics and Mining Sciences, 2003, 40:991-998.[6] SJöBERG J,CHRISTIANSSON R,HUDSON A. ISRM Suggested Methods for Rock Stress Estimation-Part 2:Overcoring Methods[J]. International Journal of Rock Mechanics and Mining Sciences, 2003, 40(7/8):999-1010.[7] 王建军.压磁套芯解除法地应力测量技术研究进展[J].岩土工程学报,1999,21(3):374-376. [8] 葛修润,侯明勋.一种测定深部岩体地应力的新方法——钻孔局部壁面应力全解除法[J].岩石力学与工程学报,2004,23(12):3923-3927. [9] 陈群策,李方全. 水力阶撑法用于原地应力测量的工作原理及其工程实践[J]. 岩石力学与工程学报,1998,17(3):305-310. [10]HAIMSON B C. Hydraulic Fracturing in Porous and Nonporous Rock and Its Potential for Determining In-situ Stresses at Great Depth[R]. Omaha: Missouri River Division, U.S. Corps of Engineers, 1968.[11]田家勇,王恩福.基于声弹理论的地应力超声测量方法[J].岩石力学与工程学报,2006,25(2):3720-3724. [12]李 远,乔 兰,孙歆硕.关于影响空心包体应变计地应力测量精度若干因素的讨论[J].岩石力学与工程学报,2006,25(10):2140-144. [13]MATSUKI K, KAGA N, YOKOYAMA T, et al. Determination of Three dimensional In situ Stress from Core Discing Based on Analysis of Principal Tensile Stress[J]. International Journal of Rock Mechanics & Mining Sciences, 2004, 41(7): 1167-1190.[14]韩晓玉,明 静,艾 凯.常用地应力测试技术评价[J].raybet体育在线
院报,2010,27(12):36-41.[15]SUGAWARA K, TAKEHARA T, OBARA Y, et al. Rock Stress Measurement by Means of the Compact Overcoring Method[J]. Journal of Mining and Materials Processing Institute of Japan, 1994,110(4): 331-336.[16]GB/T 50266—2013, 工程岩体试验方法标准[S].北京:中国计划出版社,2014.[17]SL 264—2001, 水利水电工程岩石试验规程[S].北京:中国水利水电出版社,2001.[18]BONNECHERE F. Strain Gauge for the Measurement of Axial and Radial Deformation in a Borehole[C]∥International Society for Rock Mechanics. Rock Mechanics Symposium Proceedings, Madrid, Spain, October, 1968:71-73.[19]VAN HEERDEN W L. Stress Concentration Factors for the Flat Borehole End for Use in Rock Stress Measurements[J].Engineering Geology, 1969,3(4):307-323.
基金
国家自然科学基金项目(51579016);国家重点研发计划项目(2016YFC0401801,2016YFC0401803);中央级公益性科研院所基本科研业务费项目(CKSF2016041/YT,CKSF2017037/YT)
PDF(3622 KB)
