深部岩石取芯饼化特性与形成机理研究  

Study on the Characteristics and Formation Mechanism of Deep Rock Coring Cakeization

作　　者：秦卫卫 田红卫 樊冲 马超智 QIN Weiwei;TIAN Hongwei;FAN Chong;MA Chaozhi(Shanxi Tiandi Wangpo Mining Industry Co.,Ltd.,China Coal Science and Industry Group,Jincheng 048021,China)

机构地区：[1]中国煤炭科工集团山西天地王坡煤业有限公司,山西晋城048021

出　　处：《煤》2025年第4期100-104,共5页Coal

摘　　要：深部岩芯钻取后常出现饼化现象,即岩芯断裂为饼状形貌。为探究饼化特性与形成机理,采用形貌观察、统计分析方法对饼化岩芯的宏观特性进行分析,依托扫描电镜对饼化岩芯的微观晶粒状态、晶粒结构进行分析。总结分析岩芯的饼化形成机理。结果表明:在不同条件下,饼化岩芯存在多种侧面与端面结构。直径较大的岩芯包容裂纹尖端应力的能力更强,裂隙尖端不易产生扩展,饼化岩芯数量随之减少。晶粒较小,微观缺陷发育度较高的岩芯会更易发生饼化,断口也更加光滑,厚度更小。岩性的饼化形成机理是在扰动卸压的作用下,内部残余应力释放引起侧向膨胀变形以及轴向的拉伸变形,变形过程中的质点发生位移导致微观缺陷发育并贯通为宏观裂隙。此外,原岩应力大小、初始损伤程度、钻孔在取芯过程中的扰动程度、卸压程度均对岩芯的饼化具有重要影响。In order to explore the characteristics and formation mechanism of pie formation,the macroscopic characteristics of the cake core were analyzed by morphology observation and statistical analysis,and the microscopic grain state and grain structure of the cake core were analyzed by scanning electron microscopy.The cake formation mechanism of core was summarized and analyzed.The results show that under different conditions,there are a variety of side and end face structures in the cake-shaped core.Larger diameter cores have a stronger ability to tolerate the stress at the crack tip,and the fracture tip is not easy to propagate,and the number of caked cores decreases.Cores with smaller grains and higher microscopic defects will be more susceptible to cakeization,and the fractures will be smoother and thicker.The formation mechanism of lithological cake formation is that under the action of disturbance and pressure relief,the internal residual stress release causes lateral expansion deformation and axial tensile deformation,and the displacement of the particle points in the deformation process leads to the development of microscopic defects and penetrates into macroscopic fractures.In addition,the magnitude of the original rock stress,the degree of initial damage,the degree of disturbance in the process of boring,and the degree of pressure relief all have important effects on the cakeization of the core.

关 键 词：深部岩石 岩芯饼化 钻孔取芯 扰动卸压 

分 类 号：TU452[建筑科学—岩土工程]