Abstract Long-term delayed strain of concrete impacts the lifetime of civil engineering structures such as dams, nuclear power plants, nuclear waste storage tunnels or large bridges. In design practice, the long-term delayed strain of concrete is decomposed into four components: autogenous shrinkage, basic creep, drying shrinkage and drying creep. The four components are first computed separately and then summed up to obtain the total delayed strain of concrete, without wondering about any potential correlation between them. In this work, we aim at modeling the total delayed strain in a unified manner, without assuming this decomposition a priori. Such model is derived in the framework of viscoelastic poromechanics. The influence of relative humidity on the creep properties is taken into account. We assume that drying creep is due to the fact that the mechanical consequences of capillary effects are larger in loaded drying specimens than in non-loaded drying specimens. The model is validated by comparing the prediction with experimental results of delayed strain from the literature and discussed with respect to existing models.

中文翻译：

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混凝土收缩徐变的粘弹性多孔力学模型

摘要 混凝土的长期延迟应变会影响大坝、核电站、核废料储存隧道或大型桥梁等土木工程结构的寿命。在设计实践中，混凝土的长期延迟应变分解为四个分量：自收缩、基本徐变、干缩和干徐变。这四个分量首先分别计算，然后相加以获得混凝土的总延迟应变，而无需考虑它们之间的任何潜在相关性。在这项工作中，我们的目标是以统一的方式对总延迟应变进行建模，而不是先验地假设这种分解。这种模型是在粘弹性多孔力学框架下推导出来的。考虑了相对湿度对蠕变特性的影响。我们假设干燥蠕变是由于毛细管效应的机械后果在加载的干燥样本中比在未加载的干燥样本中更大。该模型通过将预测与文献中延迟应变的实验结果进行比较来验证，并就现有模型进行了讨论。