An improved method to calculate the rock brittleness index PEECR based on linear energy storage law  

作　　者：Fengqiang Gong Yiru Zuo Song Luo Yunliang Wang 

机构地区：[1]School of Civil Engineering,Southeast University,Nanjing 211189,China [2]Southeast University-Monash University joint graduate school,Southeast University,Suzhou,Jiangsu 215123,China [3]School of Resources and Safety Engineering,Central South University,Changsha 410083,China [4]EOST-ITES,Universite de Strasbourg,Strasbourg 67000,France

出　　处：《Deep Resources Engineering》2024年第1期27-40,共14页深部资源工程（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant No.42077244).

摘　　要：The peak elastic strain energy consumption ratio(PEECR)is a rock brittleness index proposed by Gong and Wang.In the present study,based on the linear energy storage law of rock under triaxial compression,a new method was proposed to calculate the PEECR.The PEECR uses a simplified method to calculate the peak elastic strain energy.To solve this problem accurately,triaxial cyclic loading-unloading compression tests were carried out on shale.Strain energy parameters were calculated from the test curves.The results show that there is a linear relationship between the elastic strain energy and input strain energy,indicating that the linear energy storage law in rock is applicable to triaxial compression state.The universality of the linear energy storage law of rock under triaxial compression is also verified by the data in the published literature.Then,the peak elastic strain energy can be accurately determined using the linear energy storage law,and the PEECR is improved based on this.Finally,the PEECR and the improved PEECR were compared using the triaxial cyclic loading-unloading compression tests on three rocks(shale,red sandstone and granite),and the improved PEECR was compared with 11 existing energy-based brittleness indexes.The results show that the improved PEECR can further reflect the rock brittleness more accurately.

关 键 词：Rock brittleness index Linear energy storage law Peak elastic strain energy Triaxial cyclic loading-unloading compression test 

分 类 号：O57[理学—粒子物理与原子核物理]