Experimental investigation on frictional properties of stressed basalt fractures
作者机构:School of Civil EngineeringShaoxing UniversityShaoxing312000China Key Laboratory of Rock Mechanics and Geohazards of Zhejiang ProvinceShaoxing UniversityShaoxing312000China Department of Geotechnical EngineeringCollege of Civil EngineeringTongji UniversityShanghai200092China Key Laboratory of Geotechnical&Underground Engineering of Ministry of EducationTongji UniversityShanghai200092China
出 版 物:《Journal of Rock Mechanics and Geotechnical Engineering》 (岩石力学与岩土工程学报(英文版))
年 卷 期:2023年第15卷第6期
页 面:1457-1475页
核心收录:
学科分类:08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0801[工学-力学(可授工学、理学学位)]
基 金:funded by National Natural Science Foundation of China(Grant Nos.51509154 and 42077247) Natural Science Foundation of Zhejiang Province(Grant No.LGJ20E090001)
主 题:Rock friction Basalt fracture Gouge Velocity-strengthening behavior Frictional healing
摘 要:The frictional strength and sliding stability of faults are crucial in interpreting earthquake mechanisms and ***,we report friction experiments on basalt fractures,using a self-designed triaxial apparatus that allows direct shear of samples under coupled hydro-mechanical ***(VS)and slide-hold-slide(SHS)experiments are performed on both bare and gouge-bearing surfaces of Xiashan basalt subjected to cyclic shear velocities at 1e30 mm/s,effective normal stresses of 1e5 MPa,and pore pressures of 70e300 *** measured basalt friction coefficients are in the range of 0.67e0.74,which is sensitive to gouge thickness,normal stress,and ***,a reduction in friction coefficient is observed with an increment in gouge thickness,normal stress,and pore *** on the microscopic observation of the pre-and post-shearing sliding surfaces,this weakening effect in friction coefficient can be attributed to powder ***,the VS test results reveal predominantly velocity-strengthening behavior at investigated slip velocities,and this velocity strengthening behavior does not appear to be influenced by variations in normal stress,gouge thickness,and ***,changes in sliding velocity and normal stress can lead to a shift between stable and unstable ***,stable sliding is favored by high sliding velocities and low normal stress applied in this ***,we analyze the experimental data by calculating the rate-and-state parameters using the rate-and state-dependent friction(RSF)***,the calculated friction rate parameter(a-b)supports the velocity-strengthening *** frictional relaxation(Dmc)during hold periods and frictional healing(Dm)upon re-shearing are linearly proportional to the logarithmic hold time,which may be attributed to the growth in true contact area with hold *** study sheds light on the roles of sliding velocity,and gouge thickness in controlling f