Erosion and Sediment Control Tip #58

 


Shear Stress (Tractive Force) is often hard to understand.  It is the force of water that is trying to drag the channel surface downstream. This is a picture where the rock was too small, the force of the water removed the rock.  Hydraulic designs for concentrated flow areas should always include calculations to insure the channel surface will withstand the shear force of the water.

 

 

Perry L Oakes, PE

Erosion and Sediment Control Program Coordinator

AL Soil and Water Conservation Committee

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