Bridge Pier Scour Measurement by Means of Bragg Grating Arrays: Laboratory Tests and Field Applications
This paper deals with a new method to measure scour level at bridge piers. The proposed technique is based on an array of Bragg grating temperature sensors, heated by an electrical circuit. The Bragg gratings in water sense a lower temperature than those buried in the river bed, because of the different heat scattering principles in the two situations. Furthermore the response of each sensor is slower if it is buried in the bed, with respect to the case it is in water. The paper presents laboratory tests, showing the method effectiveness and reliability, and it explains the advantages with respect to other more traditional methodologies to measure scour level. Finally, the first field application is presented.
KeywordsSteady State Temperature Bridge Pier Bragg Wavelength Radio Frequency Interference Grating Pitch
Unable to display preview. Download preview PDF.
- 1.Ballio F, Orsi E, Time evolution of scour around bridge abutments, Water Engineering Research 2 4, 243-259, 2001.Google Scholar
- 2.National Cooperative Highway Research Program (NCHRP), Report 396 – Instrumentation for measuring scour at bridge piers and abutments, Transportation Board and National Research Council, 1997.Google Scholar
- 3.De Falco F, Mele R, The monitoring of bridges for scour by sonar and sedimetri, Independent Nondestructive Testing and Evaluation International 35 2, 117-123, 2002.Google Scholar
- 7.Cigada A, Ballio F, Inzoli F, Hydraulic Monitoring Unit, application for international patent n. PCT/EP2008/059075, publication n. WO/2009/013151 (2009).Google Scholar
- 10.Doebelin EO, Measurement systems: application and design, Fifth Edition (The McGraw-Hill Companies, 2004).Google Scholar