Abstract
An earlier paper by the authors discusses potential issues in the practical implementation of the Random Decrement Technique (RDT), particularly when the data has a low signal-to-noise ratio (SNR), and when filtering, which distorts the data and affects the results, is necessary. This is the case for practically every measurement of full-scale buildings, typically done at very low ambient response amplitudes. The RDT procedure used also enables a form of error quantification which allows the engineer or data analyst to judge how reliable the result is. In one of the examples in the earlier paper, it was shown that for a certain SNR, an improvement in the damping estimate is evident when the recording length is significantly longer. For the studied structure, this meant that for better results the recording had to be 72 h (or about 46,000*T where T is the building period of interest) instead of the 4 h initially considered. Even then it required a much longer record duration, estimated to be equivalent to a month of recording, to arrive at an acceptably accurate result. However, such a very long record length is impractical. The current study thus firstly aims to determine what is the minimum SNR (maximum noise level) given say just a 1-h recording, to achieve a certain level of accuracy. This is done by varying the noise level and therefore the SNRs, and applying the mentioned RDT procedure and comparing SNR against the calculated error. The SNRs of ambient response measurements of a full-scale building with and without a supplementary damping system are then viewed considering the finding on minimum SNR.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Aquino, R.E.R., Tamura, Y.: Potential pitfalls in the practical application of the random decrement technique. In: Proceedings of the 5th International Structural Specialty Conference, 2016 CSCE Annual Conference, Canadian Society of Civil Engineering, London, ON, Canada (2016)
Cole, H.A.: On-Line Failure Detection and Damping Measurement of Aerospace Structures by Random Decrement Signatures. NASA, Mountain View, CA (1973)
Cole, H.A.: Randomdec in Retrospect. CreateSpace Independent Publishing Platform, Los Altos, CA (2014)
Asmussen, J.C.: Modal analysis based on the random decrement technique – application to civil engineering structures. Ph.D. dissertation, University of Aalborg, Denmark (1997)
Jeary, A.P.: Damping in tall buildings – a mechanism and a predictor. Earthq. Eng. Struct. Dyn. 14, 733–750 (1986)
Tamura, Y., Suganuma, S.: Evaluation of amplitude-dependent damping and natural frequency of buildings during strong winds. J. Wind Eng. Ind. Aerodyn. 59(2), 115–130 (1996)
Kijewski, T., Kareem, A.: Reliability of random decrement technique for estimates of structural damping. In: Proceedings of the 8th ASCE Specialty Conference on Probabilistic Mechanics and Structural Reliability, Notre Dame, IN, USA (2000)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 The Society for Experimental Mechanics, Inc.
About this paper
Cite this paper
Aquino, R.E.R., Tamura, Y. (2019). Using the Random Decrement Technique on Short Records with Varying Signal-to-Noise Ratios. In: Pakzad, S. (eds) Dynamics of Civil Structures, Volume 2. Conference Proceedings of the Society for Experimental Mechanics Series. Springer, Cham. https://doi.org/10.1007/978-3-319-74421-6_12
Download citation
DOI: https://doi.org/10.1007/978-3-319-74421-6_12
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-74420-9
Online ISBN: 978-3-319-74421-6
eBook Packages: EngineeringEngineering (R0)