The truck escape ramp is a clump of pebbles that is located alongside downgrades. As the pebbles are randomly placed in arrester beds, few studies have been conducted on simulation methods of the irregularly shaped pebbles. This paper proposed a pebble DEM model to analyze the micro-contact mechanism of the pebbles. Based on a polynomial algorithm, the 7th fit was selected and the coefficients of the edge curves were recorded. Second, the main view and left view were filled with preset numbers of ball elements. According to the ball element parameters, the ball elements were extended to three-dimensional models. Third, based on the edges of the main view and the top view, the ball element parameters were recalculated. Then, compression tests were conducted, and the key parameters of the pebble DEM model were calibrated. Based on the built pebble DEM model, compression tests were simulated with different pressing plate velocities and laying thicknesses. The results indicate that for increases in the pressing plate velocity, the contacting forces on the plate correspondingly increase, and this increase is linearly shaped. The results for different laying thicknesses indicate that for increases in the laying thickness, the contacting forces on the plate correspondingly decrease.

中文翻译：

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卡车逃生坡道中使用的不规则形状卵石的三维离散元建模

卡车逃生坡道是一堆小石子，位于路边。由于鹅卵石随机放置在避雷器床上，因此对不规则形状鹅卵石的模拟方法进行的研究很少。本文提出了卵石DEM模型，以分析卵石的微接触机理。基于多项式算法，选择第7个拟合并记录边缘曲线的系数。其次，主视图和左视图填充有预设数量的球元素。根据球元素参数，将球元素扩展到三维模型。第三，基于主视图和顶视图的边缘，重新计算了球元素参数。然后，进行压缩测试，并校准了卵石DEM模型的关键参数。基于构建的卵石DEM模型，模拟了不同压板速度和铺层厚度的压缩试验。结果表明，随着压板速度的增加，板上的接触力相应增加，并且这种增加呈线性形状。不同铺设厚度的结果表明，随着铺设厚度的增加，板上的接触力相应减小。