Mechanical and hydraulic properties of fault rocks under multi-stage cyclic loading and unloading
Wentao Hou1
Dan Ma2
Qiang Li1
Jixiong Zhang2
Yong Liu1
Chenyao Zhou1
1.School of Mines,China University of Mining & Technology,Xuzhou 221116,Jiangsu,China2.School of Mines,China University of Mining & Technology,Xuzhou 221116,Jiangsu,China;State Key Laboratory of Coal Resources & Safe Mining,China University of Mining & Technology,Xuzhou 221116,Jiangsu,China;MOE Key Laboratory of Deep Coal Resource Mining,China University of Mining & Technology,Xuzhou 221116,Jiangsu,China
摘要：The rock mass in fault zones is frequently subjected to cyclic loading and unloading during deep resource exploitation and tunnel excavation.Research on the mechanical and hydraulic characteristics of fault rock during the cyclic loading and unloading is of great significance for revealing the formation mechanism of water-conducting pathways in fault and preventing water inrush disasters.In this study,the mechanical and seepage tests of fault rock under the multi-stage cyclic loading and unloading of axial compression were carried out by using the fluid-solid coupling triaxial experimental device.The hyster-esis loop of the stress-strain curve,peak strain rate,secant Young's modulus,and permeability of fault rock were obtained,and the evolution law of the dissipated energy of fault rock with the cyclic number of load and unloading was discussed.The experimental results show that with an increase in the cyclic number of loading and unloading,several changes occur.The hysteresis loop of the stress-strain curve of the fault rock shifts towards higher levels of strain.Additionally,both the peak strain rate and the secant Young's modulus of the fault rock increase,resulting in an increase in the secant Young's modulus of the fault rock mass.However,the growth rate of the secant Young's modulus gradually slows down with the increase of cyclic number of loading and unloading.The permeability evolution of fault rock under the multi-stage cyclic loading and unloading of axial compression can be divided into three stages:steady increase stage,cyclic decrease stage,and rapid increase stage.Besides,the calculation model of dissipated energy of fault rock considering the effective stress was established.The calculation results show that the relationship between the dissipated energy of fault rock and the cyclic number of loading and unloading conforms to an exponential function.
机标关键词：rockscyclicfaulthydraulicmechanicalmulti-stagepropertiesunder
论文发表日期：2023-08-28
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：20( 151-170 )
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