Question

Problem 4 A dam is constructed on a permeable stratum underlain by an impermeable rock. A row of sheet pile is installed at the upstream face. If the permeable soil has a hydraulic conductivity of 150 ft/ day, determine the following a. The number of potential drops, Nd b. The number of flow channels, N c. The rate of flow or seepage under the dam 40 t 16 60 t 15 14 13 12 11, 10 9 , 7, 6s 2 100

Answer 1

Counting the numbers or equipotential lines N_D = 17 Count the channels, N_f = 5 (1) = k.h N_f/N_D h = 40 - 5 = 35^1 So, phi = 150 times 35 times 5/17 = 1544.11 ft/day = 0.214 inches/sec