Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
권호 표지
DOI QR코드

DOI QR Code

Determination of Optimal Accelerometer Locations for Bridges using Frequency-Domain Hankel Matrix

주파수영역 Hankel matrix를 사용한 교량의 가속도센서 최적위치 결정

  • 강성헌 (인하대학교 토목공학과) ;
  • 신수봉 (인하대학교 사회인프라공학과)
  • Received : 2016.01.08
  • Accepted : 2016.06.22
  • Published : 2016.07.01
Download PDF
⟨ Previous Next ⟩

Abstract

A new algorithm for determining optimal accelerometer locations is proposed by using a frequency-domain Hankel matrix which is much simpler to construct than a time-domain Hankel matrix. The algorithm was examined through simulation studies by comparing the outcomes with those from other available methods. To compare and analyze the results from different methods, a dynamic analysis was carried out under seismic excitation and acceleration data were obtained at the selected optimal sensor locations. Vibrational amplitudes at the selected sensor locations were determined and those of all the other degrees of freedom were determined by using a spline function. MAC index of each method was calculated and compared to look at which method could determine more effective locations of accelerometers. The proposed frequency-domain Hankel matrix could determine reasonable selection of accelerometer locations compared with the others.

시설물의 거동 파악을 위한 대표적인 방법으로는 가속도센서에서 측정되는 동적응답을 이용하여 역해석을 통해 구조변수를 추정하는 방법이 있다. 정확한 구조변수의 추정을 위해서는 최적화된 센서의 위치가 필요한데, 본 논문에서는 다양한 최적 센서위치를 추정하는 방법을 정리하였으며, 기존 시간영역에서만 사용되었던 Hankel matrix법을 주파수영역으로 확대 개발하여 기존 최적 센서위치 추정 방법들과 결과를 비교 분석하였다. 결과 비교 및 검증을 위해 지진동에 의한 동적 해석을 수행하여 기존 및 새로운 방법으로 선택된 최적 센서위치 에서의 가속도데이터를 활용하여 FFT(Fast Fourier Transform)를 통해 진동 형상의 크기를 구하고, spline function으로 전체 자유도에 대한 진동 형상을 추정하였으며, 추정된 진동 형상과 해석적으로 구해진 진동 형상과의 MAC 지수를 통하여 다양한 방법들의 모드 추정의 정확도를 비교하였다.

Keywords

References

  1. Bayard, D. S., Fred, Y. H., and Deirdre, R. M. (1988), Optimal Experiment Design for Identification of Large Space Structures, Automatica, 24(3), 357-364. https://doi.org/10.1016/0005-1098(88)90076-3
  2. Cherng, A. P. (2003), Optimal Sensor Placement for Modal Parameter Identification using Signal Subspace Correlation Techniques, Mechanical Systems and Signal Processing, 17(2), 361-378. https://doi.org/10.1006/mssp.2001.1400
  3. Gawronski, W., and Lim, K. B. (1996), Balanced Actuator and Sensor Placement for Flexible Structures, INT. J. Control, 65(1), 131-145. https://doi.org/10.1080/00207179608921690
  4. Kang, S. (2015), Development of a Method for Dttermining Optimal Accelerometer Locations using Frequency-Domain Hankel Matrix, Master Degree Thesis, Inha University, Incheon, 1-10(in Korean).
  5. Korea Meteorological Administration (2015), Domestic earthquake trends, http://www.kma.go.kr/(in Korean).
  6. Kwon, S. J. (2006), Determination of Optimal Accelerometer Locations in Frequency Domain and Time Domain with Verification by SI Methods, Ph. D Degree Thesis, Inha University, Incheon, 4-14(in Korean).
  7. Kwon, S. J., and Shin, S. (2006), Determination of Optimal Accelerometer Locations using Mode-Shape Sensitivity, J. of the Earthquake Engineering Society of Korea, 10(6), 29-36(in Korean). https://doi.org/10.5000/EESK.2006.10.6.029
  8. Li, Y. Y., and Yam, L. H. (2001), Sensitivity Analyses of Sensor Loactions for Vibration Control and Damage Detection of Thin-Plate Systems, J. of Sound and Vibration, 240(4), 623-636. https://doi.org/10.1006/jsvi.2000.3265
  9. Liu, C., and Tasker, F. (1996), Sensor Placement for Time-Domain Modal Parameter Estimation, J. of Guidance, Control, and Dynamics, 19(6), 1349-1356. https://doi.org/10.2514/3.21793
  10. Meo, M., and Zumpano, G. (2005), On the Optimal Sensor Placement Techniques for a Bridge Structure, Engineering Structures, 27(10), 1488-1497. https://doi.org/10.1016/j.engstruct.2005.03.015
  11. Ministry of Public Safety and Security (2015), Guideline for Earthquake Acceleration Measuring Instrument, Ministry of Public Safety and Security Bulletin No. 2015-1(in Korean).
  12. Penny, J. E. T., Friswell, M. I., and Garvey, S. D. (1994), Automatic Choice of Measurement Loactions for Dynamic Testing, AIAA J., 32(2), 407-414. https://doi.org/10.2514/3.11998
  13. Zhang, L., Brincker, R., and Andersen, P. (2001), Modal indicators for Operational Modal Identification, 19th International Modal Analysis Conference (IMAC), Kissimmee, Florida.