Failure of an Earth Dam: A Case Study

In the semi-arid zones, seasonal variations in temperature and moisture content are extensive. This may induce severe cracking of the core of an earth dam, particularly in places where the soil is poorly compacted. The winter rains often result in flash floods leading to a rapid build up of reservoir level. Consequently, water flowing through the core has high gradients. Moderately dispersive soils, in such an environment, may become highly dispersive. Such a mechanism of failure has been postulated on the basis of a case study of an earth dam failure in Wadi Qattarah, Libya. Practical implications of this failure mechanism are pointed out in relation to earth dam construction practices in semi-arid zones.