The results of a research project on the dynamic behavior of fire-damaged RC structures are presented with specific reference to the fundamental period of the natural vibrations. Assessing the damage in fire-exposed RC structures is instrumental in understanding the features of the fire and in developing rational criteria to quantify structural post-fire safety. In this study, three moment-resisting frames were designed and tested to correlate the dynamic parameters with the temperature. Since the fundamental period of the natural vibrations can be easily measured for different levels of the thermal damage, the fire-induced variation of this parameter is a very efficient tool to quantify damage extension and allows introducing a novel fire damage index based on the relationship between the fundamental period and the temperature. This index is a contribution to facilitate decision-making concerning the repair and the partial or total demolition of fire-affected RC structures.

中文翻译：

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一种基于动态行为量化 RC 结构火灾致损伤的新型无损方法

一个关于火灾损坏的 RC 结构的动态行为的研究项目的结果，特别参考了自然振动的基本周期。评估暴露在火灾中的 RC 结构的损坏有助于了解火灾的特征并制定合理的标准来量化结构火灾后的安全性。在这项研究中，设计并测试了三个抗弯框架，以将动态参数与温度相关联。由于自然振动的基本周期可以很容易地测量到不同程度的热损伤，因此该参数的火灾引起的变化是量化损伤扩展的非常有效的工具，并允许引入基于之间关系的新型火灾损伤指数基本周期和温度。