Hydraulic fracturing is widely accepted and applied to improve the gas recovery in unconventional reservoirs.Unconventional reservoirs to be addressed here are with very low permeability,complicated geological setting...Hydraulic fracturing is widely accepted and applied to improve the gas recovery in unconventional reservoirs.Unconventional reservoirs to be addressed here are with very low permeability,complicated geological settings and in-situ stress field etc.All of these make the hydraulic fracturing process a challenging task.In order to effectively and economically recover gas from such reservoirs,the initiation and propagation of hydraulic fracturing in the heterogeneous fractured/porous media under such complicated conditions should be mastered.In this paper,some issues related to hydraulic fracturing have been reviewed,including the experimental study,field study and numerical simulation.Finally the existing problems that need to be solved on the subject of hydraulic fracturing have been proposed.展开更多
To analyze and predict the mechanical behaviors of deep hard rocks,some key issues concerning rock fracturing mechanics for deep hard rock excavations are discussed.First,a series of apparatuses and methods have been ...To analyze and predict the mechanical behaviors of deep hard rocks,some key issues concerning rock fracturing mechanics for deep hard rock excavations are discussed.First,a series of apparatuses and methods have been developed to test the mechanical properties and fracturing behaviors of hard rocks under high true triaxial stress paths.Evolution mechanisms of stress-induced disasters in deep hard rock excavations,such as spalling,deep cracking,massive roof collapse,large deformation and rockbursts,have been recognized.The analytical theory for the fracturing process of hard rock masses,including the three-dimensional failure criterion,stress-induced mechanical model,fracturing degree index,energy release index and numerical method,has been established.The cracking-restraint method is developed for mitigating or controlling rock spalling,deep cracking and massive collapse of deep hard rocks.An energy-controlled method is also proposed for the prevention of rockbursts.Finally,two typical cases are used to illustrate the application of the proposed methodology in the Baihetan caverns and Bayu tunnels of China.展开更多
文摘Hydraulic fracturing is widely accepted and applied to improve the gas recovery in unconventional reservoirs.Unconventional reservoirs to be addressed here are with very low permeability,complicated geological settings and in-situ stress field etc.All of these make the hydraulic fracturing process a challenging task.In order to effectively and economically recover gas from such reservoirs,the initiation and propagation of hydraulic fracturing in the heterogeneous fractured/porous media under such complicated conditions should be mastered.In this paper,some issues related to hydraulic fracturing have been reviewed,including the experimental study,field study and numerical simulation.Finally the existing problems that need to be solved on the subject of hydraulic fracturing have been proposed.
基金financial support from the National Natural Science Foundation of China(Grant Nos.51839003 and 41827806)Liaoning Revitalization Talents Program of China(Grant No.XLYCYSZX1902)。
文摘To analyze and predict the mechanical behaviors of deep hard rocks,some key issues concerning rock fracturing mechanics for deep hard rock excavations are discussed.First,a series of apparatuses and methods have been developed to test the mechanical properties and fracturing behaviors of hard rocks under high true triaxial stress paths.Evolution mechanisms of stress-induced disasters in deep hard rock excavations,such as spalling,deep cracking,massive roof collapse,large deformation and rockbursts,have been recognized.The analytical theory for the fracturing process of hard rock masses,including the three-dimensional failure criterion,stress-induced mechanical model,fracturing degree index,energy release index and numerical method,has been established.The cracking-restraint method is developed for mitigating or controlling rock spalling,deep cracking and massive collapse of deep hard rocks.An energy-controlled method is also proposed for the prevention of rockbursts.Finally,two typical cases are used to illustrate the application of the proposed methodology in the Baihetan caverns and Bayu tunnels of China.
