Abstract The influence of the microstructure on the visco-elastic properties of concrete is investigated using finite element simulations at the meso-scale. We first derive a constitutive law for the creep of the cement paste which accounts for both recoverable and permanent deformations, as well as the influence of temperature and internal relative humidity. The model is calibrated on a set of experiments at the cement paste scale, and then validated after upscaling to the concrete scale. The model is then applied to study the influence of the microstructure on the macroscopic creep of concrete. We show that materials with finer particles exhibit less creep, and that the anisotropy of creep can be explained with the shape and orientation of the aggregates. Furthermore, the acceleration of the stress relaxation in the presence of damage is explained by the micro-mechanical interaction between the aggregates, the cement paste, and the micro-cracks.

中文翻译：

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混凝土徐变模拟中的微观结构效应

摘要 在细观尺度上使用有限元模拟研究了微观结构对混凝土粘弹性能的影响。我们首先推导出水泥浆蠕变的本构定律，该定律考虑了可恢复变形和永久变形，以及温度和内部相对湿度的影响。该模型在水泥浆规模的一组实验中进行校准，然后在放大到混凝土规模后进行验证。然后将该模型应用于研究微观结构对混凝土宏观蠕变的影响。我们表明具有更细颗粒的材料表现出较少的蠕变，并且蠕变的各向异性可以用聚集体的形状和方向来解释。此外，