Step-pool system is one of the most important and widespread bed structures in mountain rivers and its failure mechanism plays a significant role on the stability and fluvial process of mountain river bed. Combined with the effects of water discharge, downstream scour of the step, surrounding grains, and grain impact, the forces acting on the keystone of a step-pool were schemed and analyzed to advance a physically-based theoretical model for individual step-pool stability. The model illustrates that the channel slope, scour angle, keystone diameter, discharge, impact grain size and interlocki...
