On the dependence of the avalanche angle on the granular layer thickness

M. Wyart

    Research output: Contribution to journalArticle


    A layer of sand of thickness h flows down a rough surface if the inclination is larger than some threshold value start which decreases with increasing h. A tentative microscopic model for the dependence of start on h is proposed for rigid frictional grains, based on the following hypothesis: i) a horizontal layer of sand has some coordination z larger than a critical value zc, where mechanical stability is lost ii) as the tilt angle is increased, the configurations visited present a growing proportion zs of sliding contacts. Instability with respect to flow occurs when z- zs=zc. This criterion leads to a prediction for start(h) in good agreement with empirical observations.

    Original languageEnglish (US)
    Article number24003
    Issue number2
    StatePublished - Aug 24 2009


    ASJC Scopus subject areas

    • Physics and Astronomy(all)

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