Innovative seismic isolation of masonry infills using cellular materials at the interface with the surrounding RC frames

Aristomenis V. Tsantilis, Thanasis Triantafillou

    Research output: Contribution to journalArticle

    Abstract

    In this study an innovative concept is proposed to isolate – at low and moderate storey drifts – infill panels from the surrounding reinforced concrete (RC) frame, using thin layers of cellular materials. The concept is verified experimentally through testing of three fully infilled (i.e. at full height) and two partially infilled (i.e. at reduced height) RC frames with different infill-to-frame interface contact conditions under in-plane cyclic loading. The shear strength, hysteretic behavior, damage evolution and stiffness degradation of conventionally infilled RC frames is compared with the respective properties of frames with isolated infills. The experimental results show that fully infilled test specimens exhibit much more severe damage than the isolated ones, leading to the conclusion that the proposed isolation system significantly preserves the integrity of infill panels at moderate storey drifts and increases shear strength and lateral stiffness of the infilled frames at higher deformations. Additional tests on frames with infills at partial height show that cellular material joints at the sides of infills decrease the adverse effects of the infill-frame interaction. Finally, it is demonstrated that mechanical properties, contact conditions and joint thickness of the cellular material influence the overall hysteretic behavior of the specimens. A simple analytical model is developed, combining single-strut elements for the infills with nonlinear springs for the cellular material joints. The model, implemented in OpenSees, is in good agreement with test results. The concept is demonstrated through parametric analyses in full scale RC structures. Overall, it is concluded that the proposed technique has a high potential in reducing infill-frame interactions – hence damage of the infills – up to moderate drifts, whereas full interaction – hence increased capacity – is still in place when drifts are large.

    Original languageEnglish (US)
    Pages (from-to)279-297
    Number of pages19
    JournalEngineering Structures
    Volume155
    DOIs
    StatePublished - Jan 15 2018

    Fingerprint

    Reinforced concrete
    Shear strength
    Stiffness
    Struts
    Concrete construction
    Analytical models
    Degradation
    Mechanical properties
    Testing

    Keywords

    • Cellular materials
    • In-plane cyclic loading
    • Infilled RC frames
    • Seismic isolation

    ASJC Scopus subject areas

    • Civil and Structural Engineering

    Cite this

    Innovative seismic isolation of masonry infills using cellular materials at the interface with the surrounding RC frames. / Tsantilis, Aristomenis V.; Triantafillou, Thanasis.

    In: Engineering Structures, Vol. 155, 15.01.2018, p. 279-297.

    Research output: Contribution to journalArticle

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