Test: Seepage Analysis - 1 - Civil Engineering (CE) MCQ

Seepage pressures, uplift pressures, exit gradient and pore-water pressure can be obtained from a flownet.

Seepage loss per metre length, 

Given, k = 4 x 10^-5 m/min
= 4 x 10^-5 x 24 x 60 m/day
= 0.0576 m/day
∴ 
= 0.1152 m³/day
= 11.52 x 10^-2 m³/day
N_f is number of flow channels = 6.0
N_d is number of equipotential drops = 18

For fine grained soils effective size ‘d’ is smaller so it will experience more capillary rise.

V_s = k_pi
Where, V_s = seepage velocity
k_p = coeff. of percolation
Seepage Velocity = Coefficient of Percolation x Hydraulic Gradient

Critical hydraulic gradient

also,

Micropores, often found between and within soil aggregates, are so small that surface tension holds water in place. It does not depend on mineral content rather depends on orientation of the particles. Instead of draining away, water moves through micropores only when suction is created by thirsty roots.