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Title |
Slow Dynamic Analysis of PCM-LWA-Mixed Concrete Plate Using Nonlinear Resonant Spectroscopy
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Authors |
김률리(Ryulri Kim) ; 최하진(Hajin Choi) |
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DOI |
https://doi.org/10.4334/JKCI.2021.33.1.021 |
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Keywords |
비선형 공진 기법; 느린 동특성; 상변화 물질; 비선형성 nonlinear resonant spectroscopy; slow dynamics; phase change materials; nonlinearity |
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Abstract |
Recent developments in nonlinear resonance spectroscopy, such as slow and fast dynamics, have enabled new levels of material evaluation for concrete. Nonlinear resonance spectroscopy has been developed with non-classical nonlinear vibration theory. Since experimental configuration requires continuous data measurements, auto impactor system was developed using solenoid and microcontroller. The vibration testing was carried out over phase change materials-light weight aggregate (PCM-LWA)-mixed concrete plate with increasing temperature, where PCM was used as light weight aggregate for improving thermal characteristics. Densely obtained data were transferred to time-frequency domain using spectrogram analysis in order to identify the frequency shift of natural frequency. The results illustrate that the developed auto impactor system is applicable to acquire high-quality data for 17 hours and spectrogram analysis possibly provides meaningful information of unique slow dynamic behaviors from PCM-LWA-mixed concrete plate. Further analysis of nonlinearity was conducted through conditioning and relaxation phase. Based on the experimental results, different vibration behaviors of PCM-LWA-mixed concrete were identified.
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