angle of repose

mechanics

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Last updated

June 18, 2026

Quick Summary

The angle of repose is a concept in physics and mechanics that describes the steepest angle at which a pile of loose material can remain stable without sliding. It is the maximum angle of slope at which a heap of granular substance, such as earth or sand, will stand without collapsing.1

This angle is determined by the friction between the particles of the material. If the slope exceeds the angle of repose, the material will begin to slide or flow downhill. This principle is important in understanding the stability of slopes, such as hillsides or piles of construction materials.2

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sand dune
Formation and growth of dunes
…slope is steepened to the angle of repose of dry sand (about 32°), this angle is maintained and the added sand slips down the slope or slip face. When this happens, the dune form is in equilibrium, and the dune moves forward as a whole, sand being eroded from the…
Read More
…slope is steepened to the angle of repose of dry sand (about 32°), this angle is maintained and the added sand slips down the slope or slip face. When this happens, the dune form is in equilibrium, and the dune moves forward as a whole, sand being eroded from the…
Read More