The balance scour depth formed by the fine sand river bed is the largest, about 1.5 times the pipe diameter, and the scour pit formed by the clay river bed has the smallest depth, about 0.5 times the pipe diameter.
The equilibrium scour depth formed by fine sand bed is the largest, about 1.5 times of the pipe diameter, while that of clay bed is the smallest, about 0.5 times of pipe diameter.<br>