Evaluation of the propensity of strain burst in brittle granite based on post-peak energy analysis

作     者：Selahattin Akdag Murat Karakus Giang D.Nguyen Abbas Taheri Thomas Bruning 

作者机构：School of CivilEnvironmental and Mining EngineeringThe University of AdelaideAdelaideSAAustralia 

出 版 物：《Underground Space》 (地下空间（英文）)

年 卷 期：2021年第6卷第1期

页      面：1-11页

核心收录：

学科分类：0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学] 

基　　金：The authors gratefully acknowledge the financial support from the Australian Research Council(ARC)(ARC-LP150100539) OZ Minerals,and the principal geotechnical manager David Goodchild.The authors also wish to thank the laboratory technicians Adam Ryntjes and Simon Golding 

主　　题：Strain burst Energy balance Class II failure mode Self-sustaining failure Triaxial compression test Circumferential strain control 

摘      要：The increasing demand for resources and depletion of near ground mineral resources caused deeper mining operations under highstress rock mass *** a result of this,strain burst,which is the sudden release of stored strain energy in the surrounding rock mass,has become more prevalent and created a considerable threat to workers and construction *** is,therefore,imperative to understand how strain burst mechanism and stored excess strain energy are affected due to the high confinement in deep underground *** this purpose,post-peak energy distributions for brittle rocks were investigated using a newly developed energy calculation method associated with acoustic emission(AE).A series of quasi-static uniaxial and triaxial compression tests controlled by the circumferential expansion were ***-back behaviour known as Class-II behaviour associated with energy evolution and the material response under self-sustaining failure were analysed on granites under a wide range of confining pressures(0–60 MPa).The experimental results underline that the energy evolution characteristics are strongly linked to *** elastic strain energy(dUE),energy consumed by dominating cohesion weakening(dUCW)and energy dissipated during mobilisation of frictional failure(dUFM)showed a rising trend as the confining pressure was *** intrinsic ejection velocity was proposed to express the propensity of strain burst that was purely determined by the excess strain energy released from Class II rock.