岩石真三轴加载破坏的热–声前兆信息链初探  

Thermal-acoustic precursor information chain of rock failure under true triaxial loading

作　　者：陈国庆[1] 张岩[1] 李阳[1] 潘元贵 金长宇[2] CHEN Guoqing;ZHANG Yan;LI Yang;PAN Yuangui;JIN Changyu(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu,Sichuan 610059,China;Key Laboratory of Ministry of Education for Safe Mining of Deep Metal Mines,Northeastern University,Shenyang,Liaoning 110819,China)

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]东北大学深部金属矿山安全开采教育部重点实验室,辽宁沈阳110819

出　　处：《岩石力学与工程学报》2021年第9期1764-1776,共13页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(41972284,41521002,42090054)。

摘　　要：硬脆性岩石的突发性失稳往往会带来灾难性的后果,因而研究硬脆性岩石突发性失稳破坏的前兆信息是十分有意义的。为此对红砂岩试样开展不同中间主应力条件下的真三轴加载试验,结合红外热像技术研究岩石破裂的热红外热像演化和温度变化特征,并借助声发射和高速摄像技术分析岩石真三轴加载下的裂纹扩展源、裂纹扩展趋势、声发射特征及破裂演化机制,提出基于热红外的非接触式岩石破裂前兆预警指标,可在岩石因破裂而导致的温度异常变化前对岩石的破坏做出预警。研究表明:岩石破裂前存在四类前兆信息,依次为热红外温度前兆、声发射前兆、热像异常前兆及岩石宏观裂纹前兆。热红外温度前兆和声发射前兆出现时间相对较早,能优先从时间上预警岩石的破坏,热像异常前兆和宏观裂纹前兆的出现时间则较晚,也距离试件破坏较近,热像异常能指示岩石未来潜在的破裂区域。从岩石的内部、外部、时间和空间上初步建立硬脆性岩石的热–声前兆信息链,研究成果可为岩石突发性失稳破坏的分析和防治提供有益参考。Sudden instability of hard brittle rock often brings disastrous consequences,so it is very meaningful to study the precursor information of sudden instability of hard brittle rock.In this paper,the true triaxial loading tests of red sandstone samples under different intermediate principal stress conditions are carried out.The thermal infrared thermal imaging evolution and temperature characteristics during rock fracture are studied adopting infrared thermal imaging technology,and the crack propagation source,crack propagation trend,acoustic emission characteristics and fracture evolution mechanism of rock under true triaxial loading are analyzed by using the acoustic emission and high-speed video technology.A non-contact pre-warning index of rock fracture based on thermal infrared is proposed,which can give early warning of rock failure before the abnormal temperature change caused by rock fracture.The results show that there are four kinds of precursory information before rock fracture,which are thermal infrared temperature precursory,acoustic emission precursory,thermal image anomaly precursory and rock macro crack precursory.The occurrence times of the thermal infrared temperature precursor and the acoustic emission precursor are relatively early,which can give priority to the early warning of rock failure.The occurrence times of the thermal image anomaly precursor and the macro crack precursor are relatively late,close to the specimen failure.Thermal image anomaly can indicate the potential fracture area of rock.In this paper,the thermoacoustic precursory information chain of hard brittle rock is established from the internal,external,temporal and spatial aspects of rock.The related research can provide a useful reference for the analysis and prevention of sudden rock failure.

关 键 词：岩石力学 岩石破裂 真三轴试验 声发射 热红外 热–声前兆 

分 类 号：TU45[建筑科学—岩土工程]