Method for predicting the shear mechanical behavior of rockfill material

Rock is a commonly utilized material in the construction of rockfill dams, protective ripraps for dam slopes, and stabilization of natural slopes. These materials demonstrate favorable performance under both static and dynamic loading conditions and are frequently more cost-effective compared to alternative stability solutions and construction methods for dams. The large dimensions and density of rock materials make it challenging to conduct representative mechanical tests and develop practical mathematical models that accurately describe their mechanical behavior at a real scale. This study proposes a hyperbolic prediction model for the shear mechanical behavior of earthfills, based on the outcomes of large-scale shear tests conducted on riprap samples with varying average dimensions (D50). Analysis of the data revealed that the hyperbolic model exhibited good agreement with the graphs depicting shear box inclination mobilized friction angle θ (°) versus shear displacement 𝛿 (mm), in relation to the riprap diameter D50. Moreover, the parameters α (Stiffness index) and β (Asymptotic index), along with the hyperbolic model, displayed a promising interrelationship of high quality.