Abstract：In orofer to know characterisic of Yewu salt mine,direct shear tests were carried out with a servocontrolled test machine RDS-200. The testing results indicate that Yewu salt rock of Pingdingshan in Henan province,for soft rocks,cohesive strength c = 3. 97 MPa,frictional angle φ = 37. 12°. Compared with the shear strength parameters of domestic salt rock,the shear strength of Yewu salt rock was slightly lower than that of Yunying salt rock; its cohesive strength was slightly higher than that of Jintan salt rock; its frictional angle was slightly lower than that of Jintan salt rock. The curves of shear stress-displacement of salt rock were relatively placid which are different from general brittle rock. Before failure stress the curves of shear stress-displacement of salt rock mainly showed linear characteristics under the high vertical stress,and the slope of the curve nearby the peak stress was small,and the peak value were not obvious. Therefore the shear dilatancy characteristics of salt rock were obvious during the specimens breakage process,and salt rock shear dilatancy end points were after peak stress. This experimental study has certain reference significance to understanding the mechanical properties of salt rock in the region,and to choosing the repository location.

Keyword：salt rock;rock mechanics;direct shear tests;shear strength;