A Study on Measurement Method of First Resonance Frequency by Non-destructive Field Test on Concrete Structures for Irrigation and Drainage

Abstract

In order to measure the first resonance frequency based on Japanese Industrial Standard, it is necessary to prepare specimens with the specific shape and size. This means that core specimens sampled from structures are required to be evaluated in their dynamic modulus of elasticity. In this study, we propose a new method for measuring the first resonance frequency in non-destructive field test. The measurement accuracy of the method and its applicability to real structures are evaluated under the conditions where a vibration generator and a wave-form recorder are separately set on the same surface. As a result, it was clarified that our method could measure the first resonance frequency with the same precision as previous testing method. Also, it was found that this method was applicable to wall-shaped members having wide surface, which are characteristic to structures for irrigation and drainage. In addition, the proposed method could evaluate the internal deformation of the above members like other existing methods.