Introducing Countermeasures for Reducing Bed Scour of Mountainous Rivers

When glaciers melt and the avalanches form, high-flow streams in steep mountainous waterways run up. Mountainous rivers have high bed slopes with gravel beds which were categorized into different reach-scale channels. Interaction between high-velocity water flow and gravel beds may wash away sediment particles and sediment transport happens. One important work in river engineering is stabilizing the river bed against erosion by reducing the bed scour. The present study introduced available methods as countermeasures for the bed scour of mountainous rivers and expressed the advantages and considerations of each technique. Seven countermeasures are presented including utilizing: grade control structures (GCS), deflector, bed sill, step pool, check dam, rock W-weir, and rock-stepped gabion weir. Investigating methods indicated that tetrahedron framed permeable weirs (TFPW) are more effective in scour reduction than beds owing to their permeability and stability and rock-W weirs, stepped gabion weirs and deflectors are eco-friendly and useful in bed stabilization. When the step pool is available it is better to have ramp segments for scour reduction. Also, scour reductions in high steep are more than in low slopes.

کلیدواژه ها:

Scour Countermeasure ، Mountainous River ، Bed Stabilization ، GCS ، Deflector