Research And Application Of Geomechanics Of Shale Layered Surface

With the success of the American shale revolution,the world is paying more and more attention to the exploration and development of shale gas.At present,the shale gas mining method is mainly horizontal well hydraulic fracturing technology.Due to the typical bedding characteristics of shale,the effects of bedding on crack initiation and propagation should be fully considered in hydraulic fracturing.In this paper,the shale failure characteristics under different bedding parameters are studied by the combination of experiment and numerical simulation.It is hoped that it can have certain significance for the efficient development of shale gas.The main research work of this paper includes the following aspects:(1)The influence of the bedding angle on the compressive strength and Young's modulus of shale is studied by uniaxial compression experiments.At the same time,experimental data were used to verify the rationality of shale as a transversely isotropic material.The mechanical parameters such as internal friction angle and cohesion of shale are obtained by triaxial compression experiments.(2)The fracture toughness of shale was tested by microindenter,and the influence of bedding angle on shale fracture toughness was summarized.(3)Using the Rock Real Failure Analysis System(RFPA),the process of shale compression failure and hydraulic fracturing failure was simulated,and the shale failure characteristics under different bedding dip angles and bedding densities were obtained.Through the research in this paper,we can help people understand that the bedding parameters have an important influence on the fracture propagation of hydraulic fracturing,and can provide some guidance for the development of shale gas.