Term: Embankment dam
**Types of Embankment Dams:**
– Earth-filled dams and rock-filled dams are the two main types of embankment dams.
– A cross-section of an embankment dam resembles a bank or hill.
– Most embankment dams have a central impermeable core made of clay, concrete, or asphalt concrete.
– Embankment dams are suitable for sites with wide valleys.
– Rock-fill dams require blasting rock and crushing it to the right size.
**Earth-fill Dams:**
– Earth-fill dams are constructed with compacted earth.
– They can be homogeneous rolled-earth dams or zoned-earth dams with distinct parts.
– Earthen dams like Tarbela Dam in Pakistan are among the largest in the world.
– They are cost-effective as local materials can be used for construction.
– Frozen-core dams are temporary structures used in high latitudes.
**Rock-fill Embankment Dams:**
– Rock-fill dams are made of compacted granular earth with an impervious zone.
– The impervious zone can be made of various materials like masonry, concrete, or asphalt.
– Rock-fill dams are resistant to earthquakes but require good quality control during construction.
– Asphalt concrete cores are popular for their flexibility and earthquake resistance.
– Concrete-face rock-fill dams use concrete slabs on the upstream face for added strength.
**Safety of Embankment Dams:**
– The weight of the water in a reservoir exerts stress on the dam.
– Overtopping of an embankment dam can lead to its failure.
– Erosion caused by overtopping runoff can destabilize the dam.
– Safety requirements for spillways are high, often designed to withstand a one-hundred-year flood.
– Various overtopping protection systems have been developed to enhance dam safety.
**Additional Resources and Publications:**
– “Devoll Hydropower Project” by Power Technology
– “Advances in rockfill structures” edited by E. Maranha das Neves
– “Shuibuya” published by Chinese Committee on Large Dams
– “Seepage Detection and Monitoring” by Maryland Department of the Environment
– Various archived and retrieved sources related to embankment dams.
An embankment dam is a large artificial dam. It is typically created by the placement and compaction of a complex semi-plastic mound of various compositions of soil or rock. It has a semi-pervious waterproof natural covering for its surface and a dense, impervious core. This makes the dam impervious to surface or seepage erosion. Such a dam is composed of fragmented independent material particles. The friction and interaction of particles binds the particles together into a stable mass rather than by the use of a cementing substance.
