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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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