Calibration and uniqueness analysis of microparameters for DEM cohesive granular material

作     者：Songtao Ji Jurij Karlovšek Songtao Ji;Jurij Karlov(s)ek

作者机构：School of Civil EngineeringThe University of QueenslandBrisbane 4067Australia 

出 版 物：《International Journal of Mining Science and Technology》 (矿业科学技术学报（英文版）)

年 卷 期：2022年第32卷第1期

页      面：121-136页

核心收录：

学科分类：0819[工学-矿业工程] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：University of Queensland, UQ China Scholarship Council, CSC 

主　　题：Discrete element method(DEM) Particle flow code(PFC) Differential evolution(DE) Parameter calibration Uniqueness analysis Post-peak behaviour 

摘      要：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 *** best calibration accuracy could reach the sum of relative errors RE_(sum)0.1%.Most calibrations can be achieved with RE_(sum)5%within hours or RE_(sum)1%within 2 *** 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 *** of more macroparameters to regulate the material mechanical behaviour that is dominated by shear crack and slip motion is highlighted for future *** DE calibration method is expected to serve as an alternative method to calibrate the DEM cohesive granular material to its peak strength.