长江科学院院报2018，Vol.35Issue(3)：13-20,8.DOI:10.11988/ckyyb.20171104
高地应力钻孔岩心饼裂特征研究
Characteristics of Rock Core Discing under High Geostress
摘要
Abstract
The rock drilling core discing in Jinping Hydro-power Station under high geostress environment is investi-gated. On the basis of summarizing the existing research results, the macroscopic failure characteristics, discing quantity,thickness and characteristics of borehole were described. The core discing mechanism and the field stress condition of the core discing were summarized through numerical simulation.Results show that:1) during the drill-ing process,the tensile stress zone crossing rock core is the dominant factor of core discing crack,and the morphol-ogy of rock disk is affected by the tensile stress in the core;2) sufficient field stress is the primary condition of core discing,and higher tensile stress is induced in the core with higher field stress,and also the condition of core disc-ing crack initiation and expansion is more adequate,and the rock disk's thickness gets smaller;3) the increase of radial field stress of borehole has a positive effect on the tensile stress induced in the drilling core, and the axial field stress is opposite;4) the average value of the maximum tensile stress cross line in the core is defined by com-paring with the tensile strength of rock,and the formula of field stress in the presence of drilling core discing is de-duced.According to the calculation,the critical condition of Jinping marble rock(T2b) discing crack is that the ra-dial field stress of borehole should be beyond 34.44 MPa.关键词
锦屏深部岩体/钻孔/岩心饼化/高地应力/岩石强度Key words
borehole/rock core discing/high geostress/Jinping deep rock mass/rock strength分类
建筑与水利引用本文复制引用
胡伟,邬爱清,陈胜宏,刘元坤,李永松..高地应力钻孔岩心饼裂特征研究[J].长江科学院院报,2018,35(3):13-20,8.基金项目
国家自然科学基金项目(51579016) （51579016）
中央级公益性科研院所基本科研业务费项目(CKSF2015047/YT) （CKSF2015047/YT）
