楔刀作用下岩石微观劣化的试验研究  

Experimental study of rock microscopic deterioration under wedge cutter

作　　者：莫振泽[1] 李海波[1] 周青春[1] 邹飞[1] 朱小明[1] 王长柏[1,2] 郝亚飞[1] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,武汉430071 [2]安徽理工大学土木建筑学院,安徽淮南232001

出　　处：《岩土力学》2012年第5期1333-1340,共8页Rock and Soil Mechanics

基　　金：国家杰出青年基金(No.51025935);国家重点基础研究发展计划(973计划)资助项目(No.2010CB732001);国家科技支撑计划项目(No.2007BAF09B01);国家科技支撑计划项目(No.2006BAB04A06)

摘　　要：通过改装RMT-150C系统,使用不同刃角的楔形刀具对花岗岩进行贯切试验,利用DISP声发射测试系统进行声发射的定位特征分析,研究岩石在楔形刀具作用下损伤劣化破坏的全过程。试验结果表明:声发射试验是一种研究TBM滚刀破岩微观机制的有效方法,脆性岩石材料的破坏过程是内部微裂纹的萌生和扩展过程的宏观反映;在楔刃刀具匀速贯入时,声发射信号随着荷载的变化呈一定对应趋势的变化,荷载-贯入度曲线能反映试件内的损伤历程;声发射2D定位结果显示,在岩石破碎区的密实核下方存在"损伤核",它由微震裂源增生丛聚分布形成,核内劣化程度高,是孕育密实核的场所,为TBM滚刀作用下岩石的宏观破裂现象提供了解释和依据;楔刀跃进式的挤压贯切岩板试件,钝刃刀具产生"球状"损伤核,尖刃刀具产生"水滴状"损伤核,钝刃刀具贯切试件产生更深的贯入度和更宽的损伤核,致使试件中不仅破碎深度大,而且破损范围广,破岩效果优于尖刃刀具。Penetrating granite specimens with different wedge cutters by changed RMT-150C system which is specially produced for indentation,and using DISP acoustic emission location system to research rock damage and physical deterioration.Acoustic emission test is an effective method to study the microscopic mechanism of rock fragmentation by tunnel boring machine（TBM） cutters.Testing results show that： rock breaking is the macro-phenomenon of internal microcrack＇s initiation and development.There is a realistic corresponding trend of load value and AE signals when wedge cutters penetrate specimens at a uniform velocity.Load-penetration curve could demonstrate the process of specimen damage.Acoustic emission plane location results show that： there is a damage core under the dense broken core,which is clustered by micro-seismic locations and is seriously deteriorated.Damage core plays a significant role to produce the next dense broken core.Experimental results provide an explanation for the macro-phenomenon of rock breaking under TBM cutter.Blunt cutter＇s indentation produces a damage core of spherical shape while sharp cutter＇s water-drop shape.Blunt cutters are better than sharp cutters to break rock specimens because of deeper penetration and wider width of damage core.

关 键 词：隧道掘进机 滚刀 破岩 声发射 损伤核 

分 类 号：TU452[建筑科学—岩土工程]