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Plate anchors are commonly used to resist static, cyclic, and monotonic post-cyclic uplift loads. Under cyclic loading, progressive sudden failure may occur, characterized by accumulated displacement--even under loads significantly less than the static capacity. Despite extensive usage of geocell materials for increasing cyclic resilience, the influence of geocell reinforcements on cyclic uplift capacity is not well understood. In this study, a series of near-full-scale experimental tests, with and without geocell, are presented. Results show that the unreinforced system fails cyclically under a load that is almost 70% of its ultimate uplift capacity ([P.sub.u]), but use of geocell enables stable cyclic resistance of over 100% [P.sub.u]. For the given soil and configurations, a cyclic displacement rate that reaches less than 0.05 mm/cycle tends to highlight a likely stable response. Evaluation of the soil's response to cyclic loading demonstrates that, with increasing loading cycles, the loading is increasingly transmitted through the soil close to the anchor in the unreinforced case, but that the reinforced case is less prone to this phenomenon. The monotonic post-cycling capacity of both reinforced and unreinforced anchors decreases after application of cyclic loading; however, the unreinforced scenario demonstrates larger decreases in capacity, particularly in the residual capacity. Key words: anchor, uplift, geocell, cyclic loading, post-cycling behavior, large-scale testing. Les ancrages a plaque sont couramment utilises pour resister aux charges statiques, cycliques et monotones apres des charges de soulevement cycliques. Sous charge cyclique, une defaillance soudaine progressive peut se produire, caracterisee par un deplacement cumule, meme sous des charges nettement inferieures a la capacite statique. Malgre l'utilisation intensive de geotextile cellulaire pour augmenter la resilience cyclique, l'influence des renforcements de geotextile cellulaire sur la capacite de soulevement cyclique n'est pas bien comprise. Dans cette etude, une serie d'essais experimentaux avec et sans geotextile cellulaire, presque a pleine echelle, est presentee. Les resultats montrent que le systeme non renforce tombe en defaillance de maniere cyclique sous une charge representant pres de 70 % de sa capacite de soulevement ultime ([P.sub.u]), mais l'utilisation de geotextile cellulaire permet une resistance cyclique stable superieure a 100 % [P.sub.u]. Pour le sol et les configurations donnes, un taux de deplacement cyclique inferieure a 0,05 mm/cycle tend a mettre en evidence une reponse probablement stable. L'evaluation de la reponse du sol a la charge cyclique montre que, lorsque le nombre de cycles de charge augmente, la charge est de plus en plus transmise a travers le sol pres de l'ancre dans le cas non renforce, mais que le cas renforce est moins sujet a ce phenomene. La capacite monotone post cyclique des ancres renforcees et non renforcees diminue apres l'application du chargement cyclique; cependant, le scenario non renforce montre des diminutions plus importantes de la capacite, en particulier de la capacite residuelle. [Traduit par la Redaction] Mots-cles : ancrage, soulevement, geotextile cellulaire, chargement cyclique, comportement post-cyclique, essais a grande echelle., 1. Introduction The stability of various structures (e.g., masts, wind turbines, rock-fall protection fences) may directly depend on anchoring that may resist static and cyclic uplift loadings. Under cyclic uplift [...]

Distributions of landslide size are hypothesized to reflect hillslope strength, and consequently weathering patterns. However, the association of weathering and critical zone architecture with mechanical strength properties of parent rock and soil are poorly-constrained. Here we use three-dimensional stability to analyze 7330 landslides in western Oregon to infer combinations of strength - friction angles and cohesion - through analysis of both failed and reconstructed landslide terrain. Under a range of conditions, our results demonstrate that the failure envelope that relates shear strength and normal stress in landslide terrain is nonlinear owing to an exchange in strength with landslide thickness. Despite the variability in material strength at large scales, the observed gradient in proportional cohesive strength with landslide thickness may serve as a proxy for subsurface weathering. We posit that the observed relationships between strength and landslide thickness are associated with the coalescence of zones of low shear strength driven by fractures and weathering, which constitutes a first-order control on the mechanical behavior of underlying soil and rock mass., (© 2022. The Author(s).)

Partial results of a NIOSH-funded study for "Protecting the Logging Workforce: Development of Innovative Logging Techniques for a Safer Work Environment" by a team of researchers at Oregon State University are presented that review safety in steep slope logging. Comparisons are made for hazards and exposures of "conventional" and new technologies for steep slopes. Hazards of new technologies are identified. Safety assessments are addressed for forestry sectors internationally, for the firm and for workers. Important questions of technical feasibility, economic viability and environmental performance are raised. Ongoing research on operators using tethered and untethered systems are described. Results will help inform training and selecting operators. New Best Operating Practices and safety code regulations will result from the research. New technologies will reduce worker hazards and exposures for steep slope logging.