Geometry and Maximum Width of a Stable Slope Considering the Arching Effect

Abstract

The stability of an arching slope in deformable materials above strong rocks strongly depends on the shape and width of the span. Equations for a free surface problem that incorporate these two parameters were derived using a simplified two-dimensional arching slope model, and were validated using physical model tests under 1g and centrifugal conditions. The results are used to estimate the maximum excavation width for a weak claystone slope in a lignite mine, for which we calculate a safety factor of 1.31.

Keywords

slope failure / geological engineering / cracked soil slope / large-scale model test / deformation mechanism / arching slope

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