Creep is a long-term deformation that can cause redistribution of stresses, large deformations, and prestress or post-tensioning losses in prestressed or post-tensioned structures, respectively. A major challenge in quantifying the effect of creep in such structures is that creep of concrete is known to continue for decades. In this paper, we examine the time-temperature superposition principle as a method to predict long-term basic creep of mature portland cement mortar from short-term creep experiments conducted at multiple elevated temperatures. For this purpose, we design a unique, miniature version of the standardized concrete creep frame to be amenable to placing in climatic chambers. We use Bažant’s B4 model to verify that the drying creep component of the measured creep behavior is negligible in comparison to the basic creep component. We develop a basic creep compliance master curve for nearly 60 years of deformation at 20 °C using experimental creep data obtained at higher temperatures for test durations of 600 days.

蠕变是一种长期变形，会分别导致预应力或后张应力结构中应力的重新分布，大变形以及预应力或后张应力的损失。量化这种结构中蠕变效应的主要挑战是已知混凝土的蠕变将持续数十年。在本文中，我们研究了时间-温度叠加原理，该方法是通过在多个高温下进行的短期蠕变实验来预测成熟硅酸盐水泥砂浆的长期基本蠕变的一种方法。为此，我们设计了一种独特的微型版本的标准化混凝土蠕变框架，以适合放置在气候室内。我们使用Bažant的B4模型来验证，与基本蠕变分量相比，测得的蠕变行为的干燥蠕变分量可忽略不计。