This document discusses several cases of dam failure including the causes, history of failures from earthquakes, and effects on human life. The key causes of dam failure discussed are overtopping from inadequate spillway design or heavy rainfall, seepage in the foundation or embankment, cracking from heavy movements or earthquakes, liquefaction, and piping which is the erosion of soil particles under the embankment. Historical examples of dam failures from earthquakes are provided from Japan, India, and California. Recommendations to prevent failure include using well-compacted materials, emergency spillways, stable slope ratios, larger dams, concrete reinforcement, and clay soils for embankments.
2. In this paper cases are discussed
1-Causes/Reasons of Dam Failure
2-Failure of Earth Fill Dames Due to Earth Quake & History
3-Effects of Dame Failure on Human Life
4-Design Faults and design safety of Dames
5-History of Dam Failure
6-Earth Fill Dams Advantages
Introduction
3. Causes of Dam Failure
1-Over Topping
1-Over Topping is due to Inadequate Spillway Design
2-Heavy rain fall or cloud burst for long time
1-Seepage in in foundation or Embankment
2-30% of All dames fails due to Seepage of water
2-Foundation Defects
3-Cracking
1-It is Caused by Heavy Movements or Vibrations
2-It is Caused by Earthquake
4-Liquifaction
The slide in the upstream shell is shown here with the
reservoir emptied. The paved road surface identifies the
former crest of the dam.
4. Causes of Dam Failure
5-Piping
Piping is Actually the erosion of
the soil particle under the
embankment which causes
collapse of embankment
6-Disaster/Earthqauke
During earthquake shaking abutments and
foundations may shift and move allowing
the dam to tilt, rotate, or slide and lose
structural integrity. Slope failures on or
near the dam may allow the reservoir to
overtop the dam or failure material to block
spillways and outlets
5. Causes of Dam Failure
5-Piping
Piping is Actually the erosion of
the soil particle under the
embankment which causes
collapse of embankment
6-Disaster/Earthqauke
During earthquake shaking abutments and
foundations may shift and move allowing
the dam to tilt, rotate, or slide and lose
structural integrity. Slope failures on or
near the dam may allow the reservoir to
overtop the dam or failure material to block
spillways and outlets
7. History & Failure of Earth Fill Dams
Date & Nomenclature Magnitude Country Dam Affected/Damage Duration
26,May 1983
Nihon-kai-Chube Earthquake
7.8 Japan Yamanaka Dam 60 Second
11-Mar-2011
Tohoku Earthquake
9.1 Japan Fujinuma Dam Caused Tsunami for 30
minutes
January 2011
Bhuj Earthquake
7.6 India Chang Dam 120 Seconds
San Francisco Earthquake 8.25
California
No Damage in 8Km
But Some Failed due
to Slope
75 Second
8. Results
1-Dames affected due to Earthquake mostly Small dames
2-Dames Resist Earthquake was Large dames
3-Dames having proper slope ratio will resist Earthquake for long time
4-Most of Dames collapse due to Liquefaction & Seepage During Earthquake
9. Conclusion and Recommendation
1-Use Best Compacted material to prevent Erosion and Seepage
2-Provide Emergency Spillways to divert the water during Flooding & Blocking of Spillway
3-Use 1:2 & 1:3 Embankment Slope which resist water pressure more efficiently
4-Construct Large dames because it resist Pressure more than small dames
5-Provide hexagonal concrete block at side slope of critical parts of Dames
6-Use Clay Soil for embankment slopes