Determination of Structural Dynamic Characteristic Using GPS Device

Document Type : پژوهشی

Authors

• mussa mahmoudi ¹
• mir Ahmad Mirghasempour ¹
• mohammad javad Najari ²

¹ Shahid Rajaee Teacher Training University.

² Shahid Rajaee Teacher Training University

10.22067/civil.v27i2.33935

Abstract

Structural dynamic parameters: natural period, shape modes and damping ratio of vibration, play a decisive role on the seismic behavior of those structures. There are several methods for determining of the structural dynamic parameters, such as: free vibration, ambient vibration and force vibration tests. In this research the structural response of a three-story building (the natural frequencies of vibration and the structural damping values) are monitored by a two-frequency GPS device mounted on the structure. The time in full oscillation of the structure will be the natural period of vibration. The damping ratio is determined using logarithmic formulation. The results from analytical method are the same as the experimental results approximately. For example, the natural period in X direction was determined 1.07 and 0.93 Hz using GPS and analytical methods. Comparing the results of the experiments and the results of the computer analysis shows the good accuracy in determining the parameters.

Keywords

• Structural Dynamic Characteristics
• Natural Period
• Natural Frequency
• Damping Ratio
• GPS

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References

. آقا کوچک، ع.، محمودی صاحبی، م.، "، بررسی خصوصیات دینامیکی ساختمان های چند طبقه با استفاده از روش آزمایش ارتعاش اجباری" ، فصلنامه مهندسی عمران و محیط زیست امیرکبیر، سال هشتم، شماره 31.

2. یادگاری، ج.، بهار ا.؛ "شناسایی پارامترهای مودال بر اساس داده های آزمایش ارتعاش محیطی با نرم افزار جدید"SIP، نشریه مهندسی عمران و نقشه برداری، دانشکده فنی، دوره ٤٤، شماره ١، صفحه ١٢١ تا 130، (١٣٨٩).

3. Park, H., Sohn, H., Kim, I., & Park, J., "Application of GPS to monitoring of wind-induced responses of high-rise buildings", Struct. Design Tall Spec. Build., vol. 17, pp. 117-132, (2008).

4. Li, X., Ge, L., Ambikairajah, E., Rizos, C., Tamura, Y. & Yoshida, A., "Full-scale structural monitoring using an integrated GPS and accelerometer system", GPS Solut, vol. 10, pp. 233–247, (2006).

5. Nickitopoulou, A., Protopsalti, K. & Stiros, S., "Monitoring dynamic and quasi-static deformations of large flexible engineering structures with GPS: Accuracy, limitations and promises", Engineering Structures, vol. 28, pp. 1471–1482, (2006).

6. Cazzaniga, N., Pinto, L., Gianfranco, F., and Abruzzi, P., "Monitoring Oscillations of Slender Structures with GPS and Accelerometers", FIG Working Week 2005 and GSDI-8 Cairo, Egypt, pp. 16-21, (2005).

7. Moschas, F. & Stiros S., "Measurement of the dynamic displacements and of the modal frequencies of a short-span pedestrian bridge using GPS and an accelerometer", Engineering Structures, vol. 33, pp.10–17, (2011).

8. Psimoulis, P., Pytharouli, S., Karambalis, D. & Stiros S., "Potential of Global Positioning System (GPS) to measure frequencies of oscillations of engineering structures", Journal of Sound and Vibration, vol. 318, pp. 606–623, (2008).

9. Ting, Y., Hong, L. & Ming G., "Effect of different construction materials on propagation of GPS monitoring signals", Journal of Measurement, vol. 45, pp.1126–1139, (2012).

10. DANA, PH., "Global Positioning System (GPS) Time Dissemination for Real-Time Applications", Journal of Real-Time systems, vol. 12, pp. 9-40, (1997).