Shear modulus

Slip (aerodynamics)

Statistics

Geotechnical engineering

Materials science

Shear (geology)

Mineralogy

Ultimate tensile strength

Calibration

Geology

Cohesion (chemistry)

Thermodynamics

Physics

Organic chemistry

Granular material

Mathematics

Mathematical analysis

Elastic modulus

Composite material

Uniqueness

Chemistry

Modulus

Stiffness

Compressive strength

International Journal of Mining Science and Technology

The differential evolution (DE) algorithm was deployed to calibrate microparameters of the DEM cohesive granular material. 4 macroparameters, namely, uniaxial compressive strength, direct tensile strength, Young's modulus and Poisson's ratio, can be calibrated to high accuracy. The best calibration accuracy could reach the sum of relative errors REsum < 0.1%. Most calibrations can be achieved with REsum < 5% within hours or REsum < 1% within 2 days. Based on the calibrated results, microparameters uniqueness analysis was carried out to reveal the correlation between microparameters and the macroscopic mechanical behaviour of material: (1) microparameters effective modulus, tensile strength and normal-to-shear stiffness ratio control the elastic behaviour and stable crack growth, (2) microparameters cohesion and friction angles present a negative linear correlation that controls the axial strain and lateral strain prior to the peak stress, and (3) microparameters friction coefficient controls shear crack friction and slip mainly refers to the unstable crack behaviour. Consideration of more macroparameters to regulate the material mechanical behaviour that is dominated by shear crack and slip motion is highlighted for future study. The DE calibration method is expected to serve as an alternative method to calibrate the DEM cohesive granular material to its peak strength.

Calibration and uniqueness analysis of microparameters for DEM cohesive granular material