大理岩穿晶裂纹起裂机制  

Nucleation of transgranular crack in marble

作　　者：程毅 陈显辉 王双 肖淑君[4] CHENG Yi;CHEN Xianhui;WANG Shuang;XIAO Shujun(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan,Hubei 430074,China;PowerChina Guiyang Engineering Corporation Limited,Guiyang,Guizhou 550081,China;Southwest Design and Research Institute Co.,Ltd.of China Airport Construction Group Corporation,Chengdu,Sichuan 610212,China;Guangzhou Urban Planning Design and Survey Research Institute,Guangzhou,Guangdong 510060,China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]中国电建集团贵阳勘测设计研究院有限公司,贵州贵阳550081 [3]民航机场建设集团西南设计研究院有限公司,四川成都610212 [4]广州市城市规划勘测设计研究院,广东广州510060

出　　处：《岩石力学与工程学报》2025年第2期303-315,共13页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金面上项目(42177161);湖北省自然科学基金资助项目(2022CFB105)~。

摘　　要：微裂纹起裂机制是岩石力学的基本问题之一,不同岩石可能表现出不同的微裂纹起裂机制。以房山、郴州和贺州3种大理岩为研究对象,先进行压缩试验及试样处理,再利用显微镜观察穿晶裂纹起裂机制。结果显示存在8种穿晶裂纹起裂机制,其中凹形边界机制、解理起裂机制、弹性不匹配机制为3种大理岩的共有机制;而双晶交叉机制、晶内双晶滑移机制和相邻颗粒双晶滑移机制仅发育于贺州大理岩中,云母解理滑移机制仅存在于郴州大理岩中,边界滑移机制只在房山和贺州大理岩中。进一步的讨论表明密集的颗粒排列、平直的颗粒边界、较弱的颗粒间胶结有利于凹形边界机制与边界滑移机制的出现;与双晶相关的起裂机制(颗粒屈服、双晶交叉、晶内双晶滑移、相邻颗粒双晶滑移)主要出现在方解石矿物中;沿解理面起裂的情况较为普遍,但由解理滑移产生穿晶裂纹的情况目前却只存在云母中。研究不仅展示不同大理岩中穿晶裂纹起裂的异同点,也说明各类起裂机制的主导因素,有助于对岩石微裂纹产生方式进行预判。The mechanism of microcrack nucleation is one of the fundamental issues in rock mechanics,and different rocks can exhibit different mechanisms.In this study,transgranular crack nucleation in three kinds of marbles from Fangshan,Chenzhou and Hezhou are observed under microscope after compression experiment.Observation identifies 8 types of transgranular crack nucleation mechanisms,among which the mechanisms of concave boundary,cleavage damage and modulus mismatch operate in all three kinds of marbles.The mechanisms of intersection of twins,twin slip in-grain or in the adjacent grain,operate only in Hezhou marble,the mechanism of cleavage slip only exists in Chenzhou marble,and the mechanism of boundary slid operates in both Fangshan and Hezhou marbles.Further discussion shows that dense grain arrangement,flat grain boundary and weak intergranular cementation are favorable to the mechanisms of concave boundary and boundary slip.Transgranular crack nucleation mechanisms related to twin,i.e.,grain yield,twin intersection,twin slip in-grainor in the adjacent grain,mainly occur in calcite. It is common for all kinds of rocks to produce transgranularcracks due to crack along the cleavage,but only exists in mica to produce transgranular cracks due to cleavageslip. The above conclusions not only show the similarities and differences of transgranular crack nucleation indifferent marbles,but also explain the dominant factors of various cracking mechanisms,which is helpful topredict the formation mode of rock microcracks.

关 键 词：岩石力学 大理岩 穿晶裂纹 起裂机制 双晶 解理 

分 类 号：TU45[建筑科学—岩土工程]