Evaluation of the time variation of the soil-structure interaction using permanent building array.

Titre : Variation temporelle des caractéristiques dynamiques des structures en lien avec l’interaction sol-structure - Evaluation of the time variation of the soil-structure interaction using permanent building array.
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Laboratoire de rattachement : ISTerre

Encadrant : Philippe GUEGUEN

Téléphone : 04.76.63.54.88

Mots clés : monitoring, dynamique des structures, risque sismique

Contexte et objectifs de la mission de stage :

The characterization and monitoring of buildings is an issue that has attracted the interest of many sectors over the last two decades. With the increasing use of permanent, continuous and real-time networks, ambient vibrations can provide a simple tool for the identification of dynamic building parameters. This study is focused on the long-term variation of frequency and damping in several buildings, using the Random Decrement Technique (RDT) (Mikael et al., 2012). RDT provides a fast, robust and accurate long-term analysis and improves the reliability of frequency and damping measurements for structural health monitoring. In parallel, experimental methods for SSI assessment exist, providing information on the rocking, drift and bending modes of the building response.
The main goal of the Master thesis will be focused on the analysis of the frequency and damping variations in time, including the soil-structure interaction. Experimental data will be used, provided by the French national Building Array Program of the National Accelerometric Networks, and by the US CSMIP database for the strongest earthquakes recorded in California. The relation between the damping and frequency wandering as well as the effect of external forcing (air temperature, soil condition etc...) will be analysed in depth.

References

Mikael A., Guéguen P., Bard P.-Y., Roux P., Langlais M. 2013. Long-term frequency and damping wandering in buildings analysed using the Random Decrement Technique (RDT), Bull seism. Soc. Am., 103(1) : 236-246, doi 10.1785/0120120048

Prérequis : étudiant motivé avec une bonne capacité de travail et d’autonomie et de bonnes connaissances en traitement du signal. Traitement et programmation sous matlab.