Hajivand Dastgerdi Rashid, Malinowska Agnieszka A
Faculty of Geo-Data Science, Geodesy, and Environmental Engineering, AGH University of Krakow, 30-059 Kraków, Poland.
Materials (Basel). 2024 Sep 30;17(19):4833. doi: 10.3390/ma17194833.
The discrete element method (DEM) has emerged as an essential computational tool in geotechnical engineering for the simulation of granular materials, offering significant advantages over traditional continuum-based methods such as the finite element method (FEM) and the finite difference method (FDM). The DEM's ability to model particle-level interactions, including contact forces, rotations, and particle breakage, allows for a more precise understanding of granular media behavior under various loading conditions. However, accurate DEM simulations require meticulous calibration of input parameters, such as particle density, stiffness, and friction, to effectively replicate real-world behavior. This study proposes a simplified calibration procedure, intended to be conducted prior to any granular material flow DEM modeling, based on three fundamental physical tests: bulk density, surface friction, and angle of repose. The ability of these tests, conducted on dry quartz sand, to accurately determine DEM micromechanical parameters, was validated through numerical simulation of cylinder tests with varying height-to-radius ratios. The results demonstrated that this calibration approach effectively reduced computational complexity while maintaining high accuracy, with validation errors of 0% to 12%. This research underscores the efficacy of simplified DEM calibration methods in enhancing the predictive reliability of simulations, particularly for sand modeling in geotechnical applications.
离散元法（DEM）已成为岩土工程中模拟颗粒材料的重要计算工具，与传统的基于连续介质的方法（如有限元法（FEM）和有限差分法（FDM））相比具有显著优势。离散元法能够对颗粒级相互作用进行建模，包括接触力、旋转和颗粒破碎，从而更精确地理解颗粒介质在各种加载条件下的行为。然而，精确的离散元法模拟需要对输入参数进行细致校准，如颗粒密度、刚度和摩擦力，以有效复制实际行为。本研究基于三项基本物理测试：堆积密度、表面摩擦力和休止角，提出了一种简化校准程序，旨在在进行任何颗粒材料流动离散元法建模之前进行。通过对不同高径比圆柱试验的数值模拟，验证了在干石英砂上进行的这些测试准确确定离散元法微观力学参数的能力。结果表明，这种校准方法在保持高精度的同时有效降低了计算复杂度，验证误差为0%至12%。本研究强调了简化离散元法校准方法在提高模拟预测可靠性方面的有效性，特别是在岩土工程应用中的砂土建模方面。
