a, The flow rate is given by q = k x H x N_{f} / N_{d}
k = 8 x 10^{-4} cm/sec
H = 5-1= 4 m
Nf = 4
Nd = 14
q = 8 x 10^{-4} x 10^{-3} x 4 x 4/14 = 9.143 x 10^{-7} m^{2}/sec per metre of dam out of plane
= 9.143 x 10^{-7} x 3600 x 24 = 0.0789942 m2/day per metre out of dam out of plane
b.
Nf = 14
Head drop = 16/14 = 1.143m per equipotential drop;
Head at point A = 16- 3x1.143 = 12.571
Head at point B=16- 5x1.143 = 10.258
Head at point C= 16-9x1.143= 5.713
c.
FS against uplift faillure for this dam= i_{critical}/i_{actual ;}
i_{critical =} (G-1)/(1+e) = (2.7-1)/(1+0.85) = 0.865
i_{actual = }4/(11x1) = 0.3636
FS against uplift failure = 0.865/0.3636 = 2.379
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