| Summary |
In order to understand the vibration characteristics of the lenticular double pneumatic membrane structures, sound pressure excitation experiment using sine wave sound from a speaker, was conducted. The test specimen was fabricated by stretch forming ETFE film. A sweep excitation experiment was conducted to determine the resonant frequency by changing the fluctuating frequency of the excitation force over time and to estimate the natural frequency. The natural frequencies in the vertical first mode obtained from the measurement results were consistent with those from the eigenvalue analysis. As a result of estimating the damping factor by the RD method, it was estimated that the damping factor was a maximum of 0.24 %. This paper reports on the experimental procedures and the results of the vibration measurements.
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