There is a need of reducing the uncertainty in traffic loading-induced settlements within railway embankments. A previously developed model for unbound stone-based materials has been implemented for modelling rockfill embankments. Particles were represented by simple breakable tetrahedral clumps of spheres with four asperities each. Both corner breakage and particle splitting were allowed. Embankments with heights between 2 and 10 m were generated by successive dumping and compaction of layers of clumps on top of each other, mimicking the construction of real embankments. Cyclic loading of the embankments representing railway traffic, for both breakable and unbreakable assemblies, was carried out. Results show that the mechanical response is marked by a substantial degree of uncertainty exacerbated by particle degradation, especially for intermediate to high embankments. An analysis of particle rotation showed that particle rearrangement mostly accumulates in the top layers, resulting in a lack of influence of embankment height on settlements. Breakage, even being of (very) limited magnitude, had a statistically significant effect. Good agreement with common geostatic theories predicting horizontal pressures was also observed. Regarding resilient response, linear stiffening with embankment height is observed with a minor influence of breakage. All in all, it is shown that the specific scale, boundary and stress conditions of embankments results in a behaviour deviating from that observed under triaxial conditions. Therefore, the key contribution is showing that it is possible to realistically model high rockfill embankments under a large number of loading cycles and furthermore including degradation, something not attempted to date.

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中文翻译：

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堆石铁路路堤的离散元建模

需要减少铁路路堤内交通负荷引起的沉降的不确定性。已实现了以前开发的未结合石材基材料的模型，用于对堆石路堤进行建模。粒子以简单的易碎的四面体球体为代表，每个球体具有四个凹凸。拐角破损和颗粒分裂均被允许。通过相继倾倒和压实彼此相叠的块状层，生成了高度在2至10 m之间的路堤，模拟了真实路堤的构造。对易碎组件和不易碎组件都进行了代表铁路交通的路堤的循环加载。结果表明，机械响应的特征是颗粒降解加剧了不确定性，特别是对于中高路堤。对颗粒旋转的分析表明，颗粒重排大多聚集在顶层，导致路堤高度对沉降的影响不大。破损，甚至是非常有限的破损，都有统计学上的显着影响。还观察到与预测水平压力的常规静压理论的良好一致性。关于弹性响应，观察到随着路堤高度的线性加劲，而断裂的影响很小。总而言之，表明路堤的特定尺度，边界和应力条件导致其行为不同于在三轴条件下观察到的行为。所以，

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