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To obtain the physical parameters and contact parameters of discrete element modelling (DEM) for simulating soil and interaction between soil and soilengaging components in mulberry field, a method combining the experiments and the DEM simulations for calibrating the contact parameters of soil particles in mulberry field was proposed. Firstly, the particle size distribution and physical parameters of soil, such as the angle of repose of soil, sliding friction angle of soil and 65Mn steel, shear stress of soil, cohesion and angle of internal friction of the soils sampled at different depths in the mulberry field, were measured respectively with the powder instrument, inclinometer and equal strain direct shear apparatus. Then an unequal-diameter sphere particles model was built according to the measured particle size distribution by using the EDEM. On this basis, the coefficient of the static friction, coefficient of rolling friction and coefficient of restitution between soil particles and between soil and 65Mn steel were used as test factors, and the angle of repose of soil and the sliding friction angle between the soil and 65Mn steel were used as target values to construct a central combined experimental design (CCD) scheme (three factors and five levels). Subsequently, by analyzing with the Design-Expert software, the simulated optimum values of the coefficient of static friction, coefficient of rolling friction and coefficient of restitution between soils were calibrated to be 0.89, 0.45 and 0.43, respectively; the simulated optimum values of coefficient of static friction, coefficient of rolling friction and coefficient of restitution between soil and 65Mn steel were calibrated to be 1.15, 0.05 and 0.4, respectively. The simulation experiments for verifying the values of the angle of repose of mulberry field soil and the sliding friction angle between the mulberry field soil and 65Mn steel were performed with the simulated parameters such as the coefficient of static friction, coefficient of rolling friction as well as coefficient of restitution. The simulating results showed that the relative errors between the simulating values and the experimental values for the angle of repose and for the sliding friction angle between the mulberry field soil and 65Mn steel were 1.69% and 2.88%, respectively. On the basis of these simulating results, using the soil shear stress gained from the experiments as the judgment standard, the bond parameters of the Hertz-Mindlin with the Bonding contact model for describing the particles of soils were calibrated with the trialanderror method with measured soil internal friction angle as the target value. The normal bond stiffness and the tangential bond stiffness were calibrated to be 1×108N/m3 and 5×107N/m3, both of the critical normal stress and the critical tangential stress was calibrated to be 10 kPa, and the contact radius was 1.1 time of radius of the particles, the simulating angle of the internal friction was 30.24°, the relative error between the simulation value and the experimental value of the angle of internal friction was 5.53%.