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Submitted by:Sharad Jha 10102055
Rudraksh Rajeev 10102083
Under the guidance of:
Prof. Dr. S. K. Singh
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They are trapezoidal in shape
Earth dams are constructedwhere the foundation or theunderlying material or rocksare weak to support the
masonry dam or where thesuitable competent rocks areat greater depth.
Earthen dams are relatively
smaller in height and broad atthe base
They are mainly built withclay, sand and gravel, hence
they are also known as Earthfill dam or Rock fill dam
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On the earth, most of thedams constructed so far are earthen dams.Failure of a number of earthen dams is due tofaulty design. The design of different
components of earthen dam has beennarrated in this paper. This will help in betterunderstanding of design of dams and damfailures.
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Project formulation
Designing of earthen dam
Check against various forms of
failures
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imensions Of Earthen am
Length -> 1,951 m
Height -> 133 m
Elevation at crest -> 435.86 m
Width (crest) -> 13.72 m
Width (base) -> 610 m
Dam volume -> 35,500,000 m3
Spillways -> 6 x radial gates
Spillway type -> Overflow gate chute
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Spillway capacity -> 12,375 m3/sTotal capacity -> 8,570,000,000 m3
Active capacity -> 7,290,000,000 m3
Catchment area -> 12,560 km2
Surface area -> 260 km2
Max. length -> 41.8 km
Normal elevation -> 426.72 m
Hydraulic head -> 95.1 m
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Soil Data
Particulars ImperviousSoil PerviousSoil oundationSoilDry Weight 17.266
kN/m3- -
Moist
Weight
19.620
kN/m3
20.405
kN/m3
20.405
kN/m3Submerged
Weight10.448kN/m3
11.085kN/m3
11.085kN/m3
SaturatedWeight
20.258kN/m3
20.895kN/m3
20.895kN/m3
Angle OfInternalFriction
20 degrees 30 degrees 30 degrees
Cohesion 42.183kN/m2
- -
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Safe against overtopping during occurrenceof flood
Seepage line must be well within the d/s face
u/s and d/s slopes should be stable undercritical and adverse condition
Foundation shear stresses within safe limits
No opportunity of free passage of water from
u/s to d/s Safe against piping
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Freeboard and cut off Core
Casing
Internal drainage system and
foundations
Side slope and Slope protection
Surface drainage
Impervious blanket
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Hydraulic failures
Overtopping
Erosion of upstream slope by waves
Erosion of d/s slope by wind and rain
Erosion of d/s toe
Seepage failures
Piping through dam and its foundation
Conduit leakage
Sloughing
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Structural failuressliding of u/s and d/s slopes
Flow slides due to spontaneous
liquefaction
Damage caused by borrowing of animals
Damage caused by water soluble
materials
Damage caused by earthquake
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