岩石脆性破坏表征与Weibull分布适用范围  

Characterization of brittle failure of rock and limitation of Weibull distribution

作　　者：陈竑然 秦四清[1,2] 薛雷 杨百存[1,2] 张珂 吴晓娲[3] CHEN Hong-ran;QIN Si-qing;XUE Lei;YANG Bai-cun;ZHANG Ke;WU Xiao-wa(Key Laboratory of Shale Gas and Geoengineering, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China;University of Chinese Academy of Scienees, Beijing 100049, China;Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education, Beijing University of Technology, Beijing 100124, China)

机构地区：[1]中国科学院地质与地球物理研究所中国科学院页岩气与地质工程重点实验室,北京100029 [2]中国科学院大学,北京100049 [3]北京工业大学城市与工程安全减灾省部共建教育部重点试验室,北京100124

出　　处：《地球物理学进展》2017年第5期2200-2206,共7页Progress in Geophysics

基　　金：国家自然科学基金项目(41572311;41302233);中国科学院战略性先导科技专项(B类)(XDB10030302)联合资助

摘　　要：理解岩石脆性破坏行为,对研究地质灾害预测、隧道安全掘进和油气储层改造等问题具有重要意义.鉴于过去关于脆性破坏的定义存在缺陷,我们认为将其定义为主要由裂纹萌生与扩展导致的破坏较为严谨.Weibull分布形状参数m可综合表征岩石的非均质性与外部环境条件作用下岩石的力学响应特征,且其数值容易测量,可作为衡量脆性破坏程度的指标.从Weibull分布的最弱环原理出发,指出该分布用于描述岩石和天然锁固段脆性破坏行为时,参数m的合理取值范围分别为[1.0,6.0)和[1.0,4.0].Understanding the brittle failure behaviour of rocks is significant to predict geological hazards, maintain safety of tunnelling and reform oil and gas reservoirs. Because the previous definition about brittle failure is imperfect,we suggest that the brittle failure can be redefined as the generation and propagation of cracks within the rock. The shape parameter m of Weibull distribution,which can be measured conveniently,represents both heterogeneity of rock and its mechanical response to loading conditions. Thus,it can be regarded as a reliable index describing the grade of brittle failures. Based on the weakest link principle by Weibull,the reasonable range of m is within [1. 0,6. 0） and[1. 0,4. 0] when the Weibull distribution is applied to analysing the brittle failure behaviour of rocks and natural locked patches,respectively.

关 键 词：脆性破坏 脆性指标 WEIBULL分布 M值 

分 类 号：P631[天文地球—地质矿产勘探]