3 m water 8 m fconcrete 2200kgm 6 in The dam shown in the f
     3 m water 8 m f)concrete = 2200kgm\" 6 in The dam shown in the figure is built of concrete having a density of 2200 kg/ m2 and rests on a solid foundation. Determine the minimum coefficient of friction between the dam and the foundation required to keep the dam from sliding at a water depth of 6.1 m. Assume that the dam is 100 m into the page.  
  
  Solution
Solution:-
Given
Density of concrete =2200kg/m3 =22 kN/m3
Height of dam = 8 m
b = 6 – (3 +1.9) =1.1 meter
Depth of water (d) = 6.1 meter
Water load produced by water weight(Fwv) = 1/2 *1.1 *6.1 *9.8 = 32.879 kN/m
Where density of water = 9.8 kN/m3
Hydrostatic force (Fwh) = 1/2 *6.1 *6.1 *9.8 =182.329 kN/m
Uplift force produced by ground water (Fu) = ½ *6.1 *6 *9.8 =179.34 kN/m
Weight of dam
W1 = 1/2 *3*8*22 =264 kN/m
W2 = 3 *8 *22 = 528 kN/m
Factor of safety = (f *V)/(H)
V =W1 +W2 +Fwv - Fu
= 264 + 528 + 32.879 – 179.34 = 645.53 kN/m
H = Fwh = 182.329 kN/m
Let factor of safety = 1.5
Friction coefficient(f) = 1.5 * 182.329/(645.53)
= 0.429 Answer

