Research on the Overall and Weak Surface Deformation Characteristics of Shale Based on CT Scan Analysis
In the process of fracturing development of shale gas horizontal wells,the casing deformation and dam-age caused by shale weak surface shear activities seriously affect the normal progress of production.Therefore,this paper investigates and analyzes the geological background of shale in Luzhou area of southern Sichuan Prov-ince under the same confining pressure and temperature,under the conditions of different pore media types and different pore pressures.The macroscopic and microscopic deformation mechanisms of shale in triaxial sliding friction experiments were explored by CT scanning technology,and experiments were carried out.The results show that in the range of pore pressure from 80 MPa to 100 MPa,the overall stereo fractal dimension of shale samples with pore pressure of 80 MPa as the medium increases the most.From 2.40 to 2.56,the curvature of shale samples with pore pressure of 100MPa and acidic solution increased the most,from 1.95 to 3.56,and the stereo-fractal dimension of samples with pore pressure of 90MPa and acidic solution decreased by 0.011 after experi-ments.On the sliding friction surface,after the experiment,the lowest increase in the fractal dimension of the slid-ing friction surface is the pressure of 80MPa.The medium is an acidic solution,which grows by 0.02879.The highest increase in the fractal dimension of the sliding friction surface was that the Y12 sample with neutral dei-onized water and pore pressure of 90 MPa increased by 0.20575.
万方数据
维普
