Abstract The most important influencing factor of rock mass strength characteristics is the discontinuities randomly distributed in rock mass. Thus,study of the mechanical properties of rock discontinuities is of great engineering significance. Based on the dynamic explicit method,the shearing failure characteristics of regular sawtooth-like structural surface is numerically simulated;and relevant model test is carried out. Comparing the numerical result with test result,the shearing failure behavior and failure patterns of normalized sawtooth-like structural surface under different normal stresses are obtained. Consequently,the applicability and reliability of the employed numerical simulation method are verified. The results indicate that:(1) Under certain normal stress,shearing failure of regular sawtooth-like structural surface develops continuously with the increase of shearing displacement,suggesting that the distribution and depth of equivalent plastic strain extended. Finally,the shearing failure reaches pure friction residual strength state. (2) The growth of rock equivalent plastic strain usually propagates from two ends to the middle gradually. For the low structural plane,shear stress is mainly distributed in the side opposite to shear velocity before reaching the peak value. After the peak value,the distribution of shear stress is uniform with increase of failure extent of structural plane. (3) When the normal stress increases,the displacement of structural plane climbing becomes more difficult and thus the failure depth increases. Thus,the failure pattern corresponding to the peak stress is becoming direct shearing sawtooth failure.
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Received: 11 January 2013
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