Abstract

This paper delivers a reliability-based method for the assessment of the elastic modulus (EM) of concrete in simply supported girders from dynamic identification. The correlation between the natural frequencies of the first bending modes and the concrete EM supports the use of the first natural frequency as a predictor of the EM value, which is a well-acknowledged indicator of the state of concrete. In the current application, the EMs of seven girders provide the prior state of knowledge about the considered bridge class, possibly to be obtained by more samples in working applications. The identified natural frequencies update the prior probability distribution of the EMs using Bayes inference. The resulting probability of exceeding a specific EM value expresses the degree of belief of the inspector in the obtained EM. The posterior probability, compared to a proper threshold, could be used in decision-making processes when prioritising the interventions in the maintenance plans.

摘要

本文提供了一种基于可靠性的方法，用于通过动态识别评估简支梁中混凝土的弹性模量 (EM)。第一弯曲模式的固有频率与混凝土 EM 之间的相关性支持使用第一固有频率作为 EM 值的预测值，这是一个公认的混凝土状态指标。在当前的应用中，七个梁的 EM 提供了关于所考虑的桥梁类别的先验知识状态，可能会通过工作应用中的更多样本获得。确定的自然频率使用贝叶斯推理更新 EM 的先验概率分布。超过特定 EM 值的结果概率表示检查员对获得的 EM 的信任程度。后验概率，