ABSTRACT This work presents the development of an ultrasonic method based on the use of multiple-scattered waves to detect and image microcracks in polymer concrete samples under steady-state bending vibrations. The sensitivity of the multiple-scattered waves to microcracks revealed to be dependent on the plane in which bending vibrations were excited. In order to understand the origin of such a sensitivity, acoustic emission measurements were performed under the same vibration conditions to verify the existence of a structural anisotropy related to microcrack distribution. Results revealed that, depending on the considered plane, acoustic emission signatures are very different and therefore can be used to understand the involved mechanisms and to identify the vibration planes that offer the optimal imaging conditions.

中文翻译：

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稳态振动条件下使用多重散射波表征聚合物混凝土中的微裂纹

摘要 这项工作提出了一种基于使用多重散射波来检测和成像聚合物混凝土样品在稳态弯曲振动下的微裂纹的超声波方法的发展。多重散射波对微裂纹的敏感性取决于激发弯曲振动的平面。为了了解这种敏感性的起源，在相同的振动条件下进行了声发射测量，以验证与微裂纹分布相关的结构各向异性的存在。结果表明，根据所考虑的平面，声发射特征非常不同，因此可用于了解所涉及的机制并识别提供最佳成像条件的振动平面。