Smart Structures and Systems

  • 제16권4호
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  • Pages.667-681
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  • 2015
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  • 1738-1584(pISSN)
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  • 1738-1991(eISSN)
테크노프레스 (Techno-Press)
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Scour-monitoring techniques for offshore foundations

  • Byuna, Yong-Hoon (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Parkb, Kiwon (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Lee, Jong-Sub (School of Civil, Environmental and Architectural Engineering, Korea University)
  • 투고 : 2014.11.21
  • 심사 : 2015.03.19
  • 발행 : 2015.10.25
⟨ 이전 논문 다음 논문 ⟩

초록

The scour induced by strong currents and wave action decreases the embedded length of monopiles and leads to a decrease of their structural stability. The objective of this study is the development and consideration of scour-monitoring techniques for offshore monopile foundations. Tests on physical models are carried out with a model monopile and geo-materials prepared in a cylindrical tank. A strain gauge, two coupled ultrasonic transducers, and ten electrodes are used for monitoring the scour. The natural frequency, ultrasonic reflection images, and electrical resistivity profiles are obtained at various scour depths. The experimental results show that the natural frequency of the model monopile decreases with an increase in the scour depth and that the ultrasonic reflection images clearly detect the scour shape and scour depth. In addition, the electrical resistivity decreases with an increase in scour depth. This study suggests that natural frequency measurement, ultrasonic reflection imaging, and electrical resistivity profiling may be used as effective tools to monitor the scour around an offshore monopile foundation.

키워드

과제정보

연구 과제 주관 기관 : National Research Foundation of Korea (NRF)

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  1. New types of time domain reflectometry sensing waveguides for bridge scour monitoring vol.26, pp.7, 2017, https://doi.org/10.1088/1361-665X/aa71f9
  2. A bundled time domain reflectometry-based sensing cable for monitoring of bridge scour pp.15452255, 2019, https://doi.org/10.1002/stc.2345
  3. Scour Protections for Offshore Foundations of Marine Energy Harvesting Technologies: A Review vol.9, pp.3, 2015, https://doi.org/10.3390/jmse9030297
  4. Applicability and limitations of time domain reflectometry bridge scour monitoring system in general field conditions vol.20, pp.3, 2015, https://doi.org/10.1177/1475921720944587