WHAT ARE THE BASIC COMPONENTS OF AN EARTH DAM?

An earth dam consists of three basic components, viz.

  1. foundation
  2. core or (membrane)
  3. oyster
  4. Transition Filter
  5. internal drain
  6. toe groove
Components of Earth Dam
Components of Earth Dam

1. foundation

It consists of either earth or rock and provides a support for the embankment and resists both vertical and horizontal loads. It also prevents seepage of water on the flow below the dam.

2. core or membrane

This dam holds back the free water of the reservoir. It is located either in the center or upstream from the center of the dam. In case of rock fill dams, the core is provided at the upstream face. To resist under-seepage, the core is extended into the foundation until an impermeable layer of sufficient thickness is reached. The expansion of the core in the foundation is called a cut off,

3. oyster

It provides structural support for the core and distributes the load on the foundation. Those dams which are made of the same material are called homogeneous dams. Small dams can be suitably constructed as homogeneous dams if the available material is suitable.

4. Transition Filter

In core dams, a transition filter Between the core and the shell is provided to prevent the migration of fine-grained core material into the pores of the generally coarse-grained shell material. In case of difference in particle size of core and shell material, the transition filter is omitted but in case of soil cover and rock or gravel shell, a transition filter is necessarily provided.

5. internal drain

One internal drain The downstream side of the dam is provided to prevent seepage through the core and cut-off, and also to prevent saturation of the downstream shale by rain on the dam.

6. toe groove

a toe groove The bottom side of the shell is provided. a ballast or hoarse Provided to cover upstream face to prevent erosion or washing by waves.



Er. Mukesh Kumar

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Er. Mukesh Kumar is Editor in Chief and Co-Funder at ProCivilEngineer.com Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.