This article aims to present a procedure to take into account the variability of the time‐dependent behavior of concrete on its structural effects, evaluated from the study of creep and shrinkage based on experimental data obtained on‐site. For this purpose, the São João Bridge, a railway bridge built in Porto, Portugal in 1991, is presented as a case study. São João Bridge is a railway bridge crossing the river Douro. It is a prestressed concrete structure, with a total length of 1,028 m, including the main span of 250 m, two side spans of 125 m, six approaching spans on the left river bank, and three approaching spans on the right river bank (Porto). During bridge construction, a comprehensive structural health monitoring (SHM) system was set up, as well as an on‐site study of time‐dependent behavior of concrete. This study was based on creep 15 specimens and 15 shrinkage specimens, prepared simultaneously with some segments of the deck, using the same material, and it was kept running during almost 20 years. The results of this study were treated statistically and used as random variables in a probabilistic analysis of the time‐dependent behavior of the bridge. After a brief description of the mentioned on‐site study and the bridge SHM system, the paper presents the procedure followed on the bridge numerical probabilistic analysis. Finally, the values computed by the numerical model are presented and compared with the experimental values provided by the SHM.

中文翻译：

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基于混凝土时变行为现场研究的圣若昂桥概率结构分析

本文旨在提出一种程序，以考虑混凝土随时间变化的行为对其结构影响的可变性，该过程是基于现场获得的实验数据，通过对蠕变和收缩的研究进行评估的。为此，本文介绍了SãoJoão桥，这是1991年在葡萄牙波尔图建造的铁路桥。圣若昂桥是穿越杜罗河的铁路桥梁。它是一种预应力混凝土结构，总长度为1,028 m，包括主跨250 m，两个侧跨125 m，左河岸六个跨距和右河岸三个跨距（波尔图） ）。在桥梁施工过程中，建立了一个全面的结构健康监测（SHM）系统，并对混凝土随时间变化的行为进行了现场研究。这项研究基于使用相同材料在甲板的某些部分同时准备的15个试样和15个收缩试样进行的蠕变研究，并且将其运行了将近20年。本研究的结果经过统计学处理，并用作桥梁随时间变化行为的概率分析中的随机变量。在简要介绍了上述现场研究和桥梁SHM系统之后，本文介绍了桥梁数值概率分析所遵循的程序。最后，介绍了由数值模型计算出的值，并将其与SHM提供的实验值进行了比较。本研究的结果经过统计学处理，并用作桥梁随时间变化行为的概率分析中的随机变量。在简要介绍了上述现场研究和桥梁SHM系统之后，本文介绍了桥梁数值概率分析所遵循的程序。最后，介绍了由数值模型计算出的值，并将其与SHM提供的实验值进行了比较。这项研究的结果经过统计学处理，并用作桥梁随时间变化行为的概率分析中的随机变量。在简要介绍了上述现场研究和桥梁SHM系统之后，本文介绍了桥梁数值概率分析所遵循的程序。最后，介绍了由数值模型计算出的值，并将其与SHM提供的实验值进行了比较。