The seepage loss in cm²/sec for a hydraulic structure, if the flow net contains 5 flow lines and 9 equipotential lines and the head causing flow is 20 m, k= 2.6 x 10^-6 cm/sec is:

Question

Question

This question was previously asked in

JKSSB JE CE 2021 Official Paper Shift 3 (Held on 28 Oct 2021)

Answer 1

Concept:

Determination of seepage discharge when the medium is isotropic:

Seepage discharge is given by,

\(q = kh\frac{{{N_f}}}{{{N_d}}}\)

Where h = Hydraulic head or head difference between upstream and downstream level or head loss through the soil

Nf = Total number of flow channels = Floe lines - 1

Nd = Total number of equipotential drops = Equipotential lines -1

k = Coefficient of permeability

Calculations:

Given data

Nf = 5 - 1 = 4, Nd = 9 - 1 = 8, h = 20 m = 2000 cm

k = 2.6 × 10-6 cm/sec

∵ seepage discharge(q),

\(q = kh\frac{{{N_f}}}{{{N_d}}}\)

\(q = 2.6 × {10^{ - 6}} × 2000 × \frac{4}{{8}} \)

q = 2.60 × 10-3 cm2/sec

Download Solution PDF