An approach is devised to determine the mechanical parameters of the microstructure of Dalian limestone rockfill material (DLRM) in triaxial compression DEM simulation. The parameters of the rockfill materials include the crushing strength parameters of the particles and the mechanical contact model parameters (mesoscopic parameters). The crushing strength parameters of the particles in the DEM simulation are determined by a series of laboratory single-particle crushing tests. Weibull statistics are applied to describe the tensile strengths of the DLRM particles, and the particle size has only a slight influence on the Weibull modulus m. The size effect of the characteristic strength of the DLRM particles can be effectively described by an exponential function. The mesoscopic parameters are ascertained by the orthogonal test design and contour method. The orthogonal test design can reduce the ranges of values of the mesoscopic parameters and analyze the sensitivity of the mesoscopic parameters. The main mesoscopic parameters that affect each macroscopic response are captured by sensitivity analysis, and the mesoscopic parameters are quickly calibrated by taking advantage of the contours. The numerical simulation results obtained using the determined parameters agree with the results of the laboratory triaxial compression tests.

设计了一种在三轴压缩 DEM 模拟中确定大连石灰岩堆石料 (DLRM) 微观结构力学参数的方法。堆石料的参数包括颗粒的抗压强度参数和机械接触模型参数（细观参数）。DEM 模拟中颗粒的抗压强度参数由一系列实验室单颗粒压碎试验确定。应用威布尔统计来描述 DLRM 颗粒的拉伸强度，粒径对威布尔模量m 的影响很小. DLRM 粒子特征强度的尺寸效应可以用指数函数有效地描述。细观参数通过正交试验设计和等高线法确定。正交试验设计可以缩小细观参数的取值范围，分析细观参数的敏感性。通过灵敏度分析捕获影响每个宏观响应的主要细观参数，并利用等高线快速校准细观参数。使用确定的参数获得的数值模拟结果与实验室三轴压缩试验的结果一致。