Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses

doi:10.1007/s40948-021-00289-8

	Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses
	Xu, Lifeng 1,2; Li, Qi 1,2; Mathias, Simon A.3; Tan, Yongsheng 1,2; Yang, Duoxing 4; Fan, Chengkai 1,2
刊名	GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
	2021-11-01
卷号	7 期号:4 页码:22
关键词	Illite fault gouge Fibre Bragg grating Permeability evolution Internal strain response Stress disturbance
ISSN号	2363-8419
DOI	10.1007/s40948-021-00289-8
英文摘要	The sealing and structural stability of faults must be considered in many underground engineering endeavours, such as underground energy extraction and CO2 geological storage. In order to simultaneously study the evolution laws of fault sealing and structural stability evolution law under stress disturbance, the fault samples were first consolidated under previous effective stress (P-pre = 10 MPa) for 62 h to imitate the fault being under the ground stress; then, the effective stress (P-e) was reduced to 0.5 MPa and gradually changed to 20 MPa to imitate the stress disturbance. Permeability and strain were measured throughout the stress disturbance by the pressure pulse method and fibre Bragg grating (FBG) sensors. In particular, high-precision FBG sensors were applied inside the fault to obtain the internal strains. The test results show that: (1) when P-e < P-pre, the permeability rapidly decreased with increasing P-e, and a risk of leakage occurred. Conversely, when P-e > P-pre, fault permeability changed little as P-e increased; but the permeability was still 4.91 times that of the undisturbed state. (2) The internal and external strain monitoring results revealed that the geometric centre of fault showed tensile strain, while other monitoring points showed compressive strain most of the time. The reason for this phenomenon is the end effect, which causes the gouge particles in the middle to move to both ends. (3) The normal deformation of fault gouge not only controls the fault volumetric strain but also controls the evolution of permeability. This study provides technical and theoretical support for the evaluation of fault sealing and structural stability when faults are disturbed in underground engineering development and construction.
资助项目	National Natural Science Foundation of China[41872210] ; National Natural Science Foundation of China[41274111] ; National Natural Science Foundation of China[41874113] ; Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering[Z018002]
WOS研究方向	Energy & Fuels ; Engineering ; Geology
语种	英语
出版者	SPRINGER HEIDELBERG
WOS记录号	WOS:000698382700002
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/27937]
专题	中科院武汉岩土力学所
通讯作者	Li, Qi
作者单位	1.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Univ Durham, Dept Engn, Durham DH1 3LE, England 4.Natl Inst Nat Hazards, Minist Emergency Management Peopless Republ China, Beijing 100085, Peoples R China
推荐引用方式 GB/T 7714	Xu, Lifeng,Li, Qi,Mathias, Simon A.,et al. Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses[J]. GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES,2021,7(4):22.
APA	Xu, Lifeng,Li, Qi,Mathias, Simon A.,Tan, Yongsheng,Yang, Duoxing,&Fan, Chengkai.(2021).Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses.GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES,7(4),22.
MLA	Xu, Lifeng,et al."Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses".GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES 7.4(2021):22.