ABSTRACT This paper presents a simple microwave non-destructive method to assess the uniformity of fiber distribution in the steel fiber reinforced concrete (SFRC). To simplify the assessment, only the amplitude attenuation information is needed, but no phase information is required. The assessment can be achieved by means of the relationship between the attenuation constant and the quantity of steel fibers per unit volume in the SFRC, which is deduced based on the Maxwell–Garnett mixing rule and the Clausius–Mossotti formulation. A measurement system based on two horn antennas in a transmission arrangement is built to analyze a real building wall for the verification of the proposed method. In addition, the cosine similarity index is proposed to confirm the validity of the experiment. The obtained results imply that the presented method is effective and simple to assess the uniformity of fiber distribution.

中文翻译：

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一种评估 SFRC 中钢纤维分布均匀性的简单微波方法

摘要 本文提出了一种简单的微波无损方法来评估钢纤维混凝土 (SFRC) 中纤维分布的均匀性。为了简化评估，只需要幅度衰减信息，不需要相位信息。评估可以通过衰减常数与 SFRC 中单位体积钢纤维数量之间的关系来实现，该关系是基于 Maxwell-Garnett 混合规则和 Clausius-Mossotti 公式推导出来的。建立了一个基于传输布置中的两个喇叭天线的测量系统来分析真实的建筑物墙，以验证所提出的方法。此外，还提出了余弦相似度指数来验证实验的有效性。