The effect of side slope and clay core shape on the stability of embankment dam: Southern Ethiopia

Abstract

In a dam construction, the primary concern is the economy and stability of the dam construction, in parallel with the benefit gained from it. The Gidabo rock fill dam has nearly flatter (2H:1V) side slope with 22 m dam height from river bed level, which consume high fill material relative to this height and dam type. In this study, the effect of clay core shape and side slopes on the stability of embankment dam is analyzed and the minimum earthwork consumption with stable dam safety is identified. The identified best side slope and shape of clay core has checked for all loading condition with numerical modeling software called Geo-Studio 2012. Based on computation the factor of safety of 1.514 and 1.611 for upstream and downstream at end of construction, 1.504 for steady state condition, 1.316 for sudden drawdown and flux through the dam has been found to be 1.95 × 10−7 m3/s/m. The horizontal and vertical deformation of the dam at normal pool level is 0.023 m and 0.192 m, respectively, which are all within the allowable limit. Hence, the selected clay core shape and side slope dam fulfill all design criterion and reduce the consumption of shell fill material.