3 (a) Briefly give the theory of distribution and transporation of suspended material and derive the formula connecting the concentration of sediment and settling velocity under equilib- rium conditions. (b) Explain how sedimentation in a reservoir can be controlled. (Hint: for Q 3 (a) supplementary reading)

3 (a) Briefly give the theory of distribution and transporation of suspended material and derive the formula connecting the concentration of sediment and settling velocity under equilib- rium conditions. (b) Explain how sedimentation in a reservoir can be controlled. (Hint: for Q 3 (a) supplementary reading)

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter7: Permeability

Section: Chapter Questions

Problem 7.4P

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The static level of water table in an unconfined aquifer was 30 m above the underlying impermeablestratum. A 150 mm diameter well, penetrating the aquifer to its full depth, was pumped at the rate of20 liters per second. After several weeks of pumping, the drawdown in observation wells 20 m and 50m from the well were 3.5 m and 2 m respectively, and the observed drawdowns were increasing veryslowly (B.Sc., DU, 2012).a) Assuming equilibrium conditions, estimate the hydraulic conductivity and transmissivity of theaquifer.b) Estimate the drawdown just outside the pumped well.c) What will be the yield of a 300 mm diameter well which will produce the same drawdowns justoutside the well and at the 50 m distance observation well in (2)? What would be the drawdown at anearer observation well?
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