Event Title
Case Study: Calculating Bridge Displacement from Accelerations for Load Assessment Calculations
Location
Cork Institute of Technology, Cork, Ireland
Event Website
https://event.ceri2020.exordo.com/
Start Date
27-8-2020 11:45 AM
End Date
27-8-2020 1:00 PM
Description
Recovering displacement from accelerations has been demonstrated on bridges previously, with the main challenges being the presence of low frequency noise and the need for user-calibrated filters to overcome this. Therefor this paper presents a case study of a low-cost load test procedure, using bridge acceleration to calculate displacement. Typical approaches look use filtering or signal collecting methods to mitigate noise, however this study uses an aviation grade accelerometer to minimise noise in the acceleration signals and employs a quality control procedure to alert the user to the quality/reliability of the results. A live/open bridge is tested using a loaded and unloaded truck, and direct displacements are also recorded by linear variable displacement transducer (LDVT) and Imetrum camera displacement system to verify results. The calculated displacements from the integration procedure with varied loads are presented, with the quality indicators first being assessed before comparing to the directly measured displacements. This procedure may not be applicable to longer span bridges, or bridges where it is difficult to isolate quiet periods of traffic, however for this study the procedure worked well. Overall, the quality' indicators provided good insight into the accuracy of the calculated displacements and there was good agreement between the 3 measurement methods, with the magnitudes of errors experienced being around ±0.3mm.
Recommended Citation
Bunce, Andrew; Hester, David; Taylor, Su; Brownjohn, James; and Xu, Yan, "Case Study: Calculating Bridge Displacement from Accelerations for Load Assessment Calculations" (2020). Civil Engineering Research in Ireland 2020. 5.
https://sword.cit.ie/ceri/2020/2/5
Included in
Civil Engineering Commons, Construction Engineering and Management Commons, Environmental Engineering Commons, Geotechnical Engineering Commons, Hydraulic Engineering Commons, Structural Engineering Commons, Transportation Engineering Commons
Case Study: Calculating Bridge Displacement from Accelerations for Load Assessment Calculations
Cork Institute of Technology, Cork, Ireland
Recovering displacement from accelerations has been demonstrated on bridges previously, with the main challenges being the presence of low frequency noise and the need for user-calibrated filters to overcome this. Therefor this paper presents a case study of a low-cost load test procedure, using bridge acceleration to calculate displacement. Typical approaches look use filtering or signal collecting methods to mitigate noise, however this study uses an aviation grade accelerometer to minimise noise in the acceleration signals and employs a quality control procedure to alert the user to the quality/reliability of the results. A live/open bridge is tested using a loaded and unloaded truck, and direct displacements are also recorded by linear variable displacement transducer (LDVT) and Imetrum camera displacement system to verify results. The calculated displacements from the integration procedure with varied loads are presented, with the quality indicators first being assessed before comparing to the directly measured displacements. This procedure may not be applicable to longer span bridges, or bridges where it is difficult to isolate quiet periods of traffic, however for this study the procedure worked well. Overall, the quality' indicators provided good insight into the accuracy of the calculated displacements and there was good agreement between the 3 measurement methods, with the magnitudes of errors experienced being around ±0.3mm.
https://sword.cit.ie/ceri/2020/2/5
