Conference Paper

Guidelines definition for in-situ vibration measurements of buildings

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Abstract

As an attempt to find a correlation between dynamic response of timber and timber-concrete composite floors and users’ comfort feeling, an in-situ measurements campaign will be carried out within the framework of a research project started at ESB, France. A large variability of buildings typology, as multi-unit housing, open-space offices and long-span offices with partition walls will be tested. The first experimental experience has shown that choices of means of excitation, type and positioning of sensors, data acquisition device, data analyses methods, depend on the floor configuration. Using in-situ test campaign as a database to compare different measurement protocols and assess the influence of different in-situ conditions, the paper will propose some guidelines for the measurement architecture, the equipment choice and the data analysis to be performed according to each building configuration.

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... Bui et al. [27] experimentally investigated the natural frequencies, damping ratios, and mode shapes of multilayered timber beams. Lanata et al. [28] attempted to establish correlations between the dynamic response of in situ timber and TCC floors and human comfort perception by varying building typology. ...
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La tendance architecturale actuelle favorise la construction de grands espaces modulables et évolutifs. L'utilisation de produits industriels dérivés du bois permet de construire des planchers de grandes portées. Par contre, ces structures légères se trouvent confronter à une sensibilité aux vibrations. Dans le cadre de cette étude, les vibrations des planchers sont examinées, sous les effets de l'impact du talon et de la marche. Ces sollicitations sont retenues pour apporter la connaissance du comportement dynamique du plancher, pour positionner celui-ci vis-à-vis du niveau de confort, et des critères de dimensionnement. Ainsi, les questions suivantes sont étudiées : Quels sont les principaux paramètres structurels influençant le comportement dynamique ? Quels critères faut il choisir pour dimensionner la structure selon le niveau de confort envisagé ? Comment optimiser la conception des planchers en bois en intégrant les aspects liés au confort humain? A ce jour, seul les essais expérimentaux réalisés à l'échelle de la structure constituent le moyen pour déterminer des données subjectives du confort. Pour ces cas étudiés, un lien est établi entre la perception au confort vibratoire et les caractéristiques spécifiques dynamiques du plancher. Pour viser l'extension aux multiples paramètres constructifs avec l'aide de l'expérimentation numérique en complément d'essais limités par " type de plancher ", les analyses dynamiques sont obtenues au moyen de la simulation numérique. In fine, les données structurelles à considérer dans les critères de dimensionnement sont affinées, en vue de l'établissement d'un guide de la conception et d'une aide au dimensionnement.
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