Abstract: The mechanical characteristics of shale with different beddings coring were investigated by MTS815 rock mechanical test system. The failure modes，deformation and strength characteristics are obtained. The results indicate that: (1) It shows significantly different properties, when the sample paralleled to bedding plane; it has maximum value of compressive strength and minimum value when the sample has a angle of 30° with bedding plane. The elastic modulus deceases with the increase of the coring angle. (2) Under the condition of uniaxial compression, the angle of 0°, the main failure mode is split failure along the beddings; the angle of 30°, it is shear failure along the weakness plane, the angle of 60°, it is wide-angle shear failure along the weakness plane; the angle of 90°, it is stretch-draw failure. (3) Under the condition of triaxial compression, angle of 0°, it shows several failure surfaces, combined split and shear failure actions; the angle of 30°,it shows shear failure along to the beddings; the angle of 60°, it shows shear failure and the angle of failure surface is 45° to 50°; the angle of 90°, it shows shear failure and it has several parallel failure surfaces. The results can provide an important way for fracture optimization design.

Key words: layer shale, bed plane, mechanical characteristics, failure mode