The evolution characteristics of rock fracture instability under cyclic loading on the basis of the enhanced LURR

Zhang, Shuai1; Yang, Runhai1; Tan, Junqing2; Zhang, Yan1; Jiang, Jinzhong1

2023-01-30

10.3389/feart.2022.1069046

FRONTIERS IN EARTH SCIENCE   Impact Factor & Quartile

2296-6463

Prospective discrimination of rock instability and fracture is a key problem in mining, slope stability, earthquake triggering, and other research fields. Through the rock fracture experiment, scientists put forward the load unload response ratio (referred to as LURR) to detect the non-linear deformation process of the strain stress curve, judge the degree of rock damage and instability fracture, which is accepted worldwide and has been widely used in seismic risk assessment. But, the extraction of response parameters (including strain, energy, well water level, etc.) are faced with many difficulties in actual observation, which makes the application of results uncertain. In this paper, the change of relative wave velocity is proposed as the loading unloading response parameter. Through rock mechanics experiments, a prospective discrimination method of rock instability and fracture process is constructed. The change characteristics of the LURR in the process of rock instability and fracture under stress are studied, the experiment result show that: when approaching the main fracture, the LURR calculated by taking the transverse strain energy as the response quantity obviously rises and fall back, the acoustic emission energy release rate and event rate are close to exponential acceleration process; The LURR by taking the change of relative wave velocity as the response parameter, first decreases, then fluctuates near zero, and rapidly decreases to below zero when it reaches the critical failure. The change combination of the above parameters' response ratio can effectively judge the process of rock deformation, instability and fracture under stress. Moreover, this study of the load unload response ratio which takes the change of relative wave velocity as the response parameter, makes up the deficiency of the traditional load unload response ratio method in judging the rock instability of the medium under stress.

rock experiment cyclic loading instability fracture measurement of wave velocity loading and unloading response ratio

SCI

English

Others

Open Fund of the State Key Laboratory of Seismic Dynamics[LED 2016B06] ; National Natural Science Foundation["41574059","41174043","42104060"] ; Key Research and Development Plan of Yunnan Province[202203AC100003] ; Sichuan Science and Technology Program[2020YJ0184]

Geology

Geosciences, Multidisciplinary

WOS:000935153000001

FRONTIERS MEDIA SA

Web of Science

1.Kunming Earthquake Predict Res Inst, Yunnan Earthquake Agcy, Kunming, Yunnan, Peoples R China
2.Southern Univ Sci & Technol, Dept Earth & Space Sci, Guangzhou, Peoples R China

Zhang, Shuai,Yang, Runhai,Tan, Junqing,et al. The evolution characteristics of rock fracture instability under cyclic loading on the basis of the enhanced LURR[J]. FRONTIERS IN EARTH SCIENCE,2023,10.

Zhang, Shuai,Yang, Runhai,Tan, Junqing,Zhang, Yan,&Jiang, Jinzhong.(2023).The evolution characteristics of rock fracture instability under cyclic loading on the basis of the enhanced LURR.FRONTIERS IN EARTH SCIENCE,10.

Zhang, Shuai,et al."The evolution characteristics of rock fracture instability under cyclic loading on the basis of the enhanced LURR".FRONTIERS IN EARTH SCIENCE 10(2023).