Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)
- Volume 5 Issue 4
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- Pages.215-225
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- 2001
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- 2234-6937(pISSN)
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- 2287-6979(eISSN)
Dispersive Wave Analysis of a Beam under Impact Load by Piezo-Electric Film Sensor and Wavelet Transform
충격하중을 받는 보에서 압전 필름센서와 웨이브렛 변환을 이용한 문산파동의 해석
- Received : 2000.06.23
- Published : 2001.10.31
Abstract
Stress waves monitored on the surface of structures under various loading conditions can provide useful information on the structural health status. In this paper, stress waves are measured by several sensors when a steel beam is impacted by a ball drop. The sensors used include the piezo-electric film Sensor, the electrical strain gage, and the ultrasonic transducer, and special attention is given to the pieza film sensor. The wavelet transform is used for the time-frequency analysis of dispersive waves propagating in the beam. The velocities of the wave produced in the team due to the lateral impact is found to be frequency-dependent and identified as the flexural wave velocity based on the comparisons with the Timoshenko beam theory. A linear impact site identification method is developed using the flexural wave, and the impact sites of the beam can be accurately estimated by the piezo film sensors. It is found that the piezo film sensor is appropriate for sensing stress waves due to impact and for locating impact sites in the beam.
Keywords
- Stress wave;
- Structural health status;
- Piezo film sensor;
- wavelet transform;
- Timenshenko beam theory;
- Impact site identification