Size Effect of Sandstone Particle Crushing Strength and Aggregate Shear Strength Based on Nominal Particle Size

Single particle and particle assembly are subjected to uniaxial compression tests and direct shear tests to explore the strength characteristics under different sizes, stone contents, and maximum particle sizes. Based on the Weibull statistical model, this paper establishes a formula for the size effects of particle strength. The paper statistically analyzes the nominal particle size distribution and derives a grading cure. It determines the relationship between the characteristic particle size and nominal particle size within particle assembly, leading to the modifications in the equation describing the size effects on particle assembly strength. The results show that the crushing strength of sandstone particles has a significant effect on particle size. Through the derivation of a conversion formula between the characteristic and the nominal size, an adjusted equation for strength size effects was formulated, which can better predict the strength parameters of naturally graded rock fill materials, offering valuable guidance for real-world engineering applications.