摘要
This paper presents an experimental study on single particle breakage behavior of crushable weathered sands by a number of single particle uniaxial compression tests to comprehensively investigate the characteristics of single particle breakage,the probability of survival of single particle,and the effects of particle size and weathering on single particle strengths.The behavior of single particle under uniaxial compression falls into the mixed five phases:damage by chipping,elastic deformation,fragmentation by partial fracture,breakage by splitting,and the residuals,demonstrating the complexity and variability of the tensile strengths of single particles.The behavior of single particle breakage was quantified herein by the initial fracture and failure strengths of single particle.The probability of survival decreased as the characteristic stresses increased.An increase in the particle size or weathering number of single particle resulted in a reduction in the probability of survival of single particle.For a given probability of survival,the difference in the initial fracture characteristic stress and failure characteristic stress decreased with increasing particle size but showed a complex change with increasing weathering number.The probability of survival showed greater variability for the normalized initial fracture characteristic stress than for the normalized failure characteristic stress,implying that the initial fracture stresses of single particles diverged more than the failure stresses of the particles.The average initial fracture and failure characteristic stresses,and the initial fracture and failure characteristic stresses corresponding to 1/e(37%)survival of single particles decreased while increasing particle size or weathering number,but the decrease showed a sharper rate for smaller single particles with a lower weathering number.The ln-ln coordinates showed a linear representation of the failure characteristic stress and particle size,verifying the applicability of Weibull theory to single particle breakage.However,weathering resulted in downward translation and slight rotation of the linear relation of the failure characteristic stress and particle size in the ln-ln coordinates.
基金
supported by the National Natural Science Foundation of China(Grant no.41807268)
the Youth Innovation Promotion Association of the Chinese Academy of Sciences-China(Grant no.2018408)。