The influence of the bedding angle under passive confining pressure on the dynamic strength and energy consumption of shale

Abstract

In order to analyze the strength characteristics, damage characteristics and energy dissipation laws of the bedding shale specimens under passive confining pressure, the Hopkinson Pressure Bar(SHPB)device was used to perform different impact pressures and impact test(no confining pressure and passive confining pressure).The experimental research results show that under different impact pressure gradients, the damage degree of shale increases significantly with the increase of impact pressure gradient, and the bearing capacity of specimens decreases; the passive confining pressure condition significantly improves the anti-destructive ability of shale specimens.Transitioned from brittle failure to ductile failure under the condition of no confining pressure, the yield strength of the shale specimen is increased by 2.25~3.06 times, and the axial stress peak value is 1.8~2.5 times of that under the condition of no confining pressure; under the condition of passive confining pressure, the energy dissipation of shale specimens increases linearly with the increase of the average strain rate.It has a significant strain rate correlation within the strain rate range tested in this paper(\begin{document}$\dot{\varepsilon} $\end{document} =97~520);shale has a significant transverse view Isotropic characteristics and bedding angle have significant effects on the strength characteristics, energy dissipation and damage characteristics of shale specimens.

Keywords

• shale
• bedding
• passive confining pressure
• dynamic mechanical properties
• separate hopkinson pressure bar(shpb)