The Bingham model for debris flows is given by
where is the shear stress and K is the yield strength (Johnson 1970, p. 497). Compare this with the Newtonian shear
In a semicircular channel,
for
for
is the flow thickness.
References
Bingham, E. C. Fluidity and Plasticity. New York: McGraw-Hill, 1922.
Johnson, A. M. "Debris Flows." In Physical Processes in Geology. San Francisco, CA: Freeman, Cooper and Co., pp. 433-534, 1970.
