松科二井4900~6830 m不同深度岩石非线性力学行为和取样损伤特性试验研究  

Experimental study on nonlinear mechanical behavior and sampling damage characteristics of rocks from depths of 4900−6830 m in Well Songke-2

作　　者：杨明庆 李佳南 高明忠 陈领 李聪 何志强 魏子杰 谢和平 YANG Ming-qing;LI Jia-nan;GAO Ming-zhong;CHEN Ling;LI Cong;HE Zhi-qiang;WEI Zi-jie;XIE He-ping(College of Water Resource and Hydropower,Sichuan University,Chengdu 610065,China;Institute of Deep Earth Science and Green Energy,College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China;School of Mechanical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]College of Water Resource and Hydropower,Sichuan University,Chengdu 610065,China [2]Institute of Deep Earth Science and Green Energy,College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China [3]School of Mechanical Engineering,Sichuan University,Chengdu 610065,China

出　　处：《Journal of Central South University》2023年第4期1296-1310,共15页中南大学学报（英文版）

基　　金：Projects(51827901, U2013603) supported by the National Natural Science Foundation of China;Project(2019ZT08G315) supported by the Program for Guangdong Introducing Innovative and Entrepreneurial Teams, China;Project(JCYJ20190808153416970) supported by Shenzhen Basic Research Project, China。

摘　　要：本文利用松科二井的深部岩芯开展了4900~6830 m范围内不同深度岩石的单轴压缩力学测试,详细分析了不同深度岩石的变形破坏特征规律,并基于力学测试结果揭示了深部岩石的取样损伤随埋深的变化特点。研究发现:在4900~6830 m范围内,岩石单轴压缩的各力学参数随深度非线性变化,深部岩石的强度特性与硬相矿物的含量呈正相关;单轴压缩破坏模式多为突发性的轴向拉伸劈裂,对比研究岩芯破坏断面和松科二井4500~7000 m饼化岩芯的断面,发现在两种破坏案例中岩浆岩试样的破坏断面均更加光洁;在4900~6000 m范围内,岩石峰前特征应力都随深度的增加而增大,主要受控于沉积岩的重力沉积作用;在6000~6830 m范围内,岩石特征应力随深度的增加而减小;损伤应力在不同深度岩石的应力应变曲线中位置相对稳定;利用裂纹闭合应力表征了不同深度岩石的取样损伤,发现在0~6250 m沉积岩地层中,岩芯的裂纹闭合应力随深度的增加呈线性增加趋势,而在6250~7000 m岩浆岩地层内,裂纹闭合应力随深度的增加趋于稳定。研究成果可为深地科学规律探索和深部工程实践提供参考。Based on the deep cores of Well Songke-2(SK-2),uniaxial compression tests of deep rock from 8 different depths in the 4900−6830 m range were carried out,and deformation and failure characteristics were analyzed in detail.It was found that in the range of 4900−6830 m,the mechanical parameters of uniaxial compression tests of rocks changed nonlinearly with depth,and the strength was positively correlated with the hard mineral content.Comparing the rock failure of these samples with the 4500−7000 m core disc segment in SK-2,it was found that the failure of magmatic rock samples in both cases was smoother than that of sedimentary rock,indicating that deep magmatic rocks more easily released energy during the failure process.From depths of 4900−6000 m,prepeak characteristic stresses increased with increasing depth,while from depths of 6000−6830 m,they decreased with increasing depth.Fracture closure stress was used to characterize rock sampling damage at depths of 1000−6830 m,and it was found that sampling damage varied linearly with burial depth in sedimentary strata,while in igneous strata,sampling damage remained stable with increasing burial depth.

关 键 词：松科二井 深部岩石 不同深度 单轴压缩试验 特征应力 取样损伤 

分 类 号：TU45[建筑科学—岩土工程]