Analisis Rembesan terhadap Bahaya Piping pada Bendungan Way Sekampung

Abstract

Piping due to internal erosion can lead to structural failure of the embankment dam. The initial piping which is formed at downstream-toe side of the dam is influenced by the critical gradient of the material (Ic) and the exit gradient (Ie). Piping will start to form if the ratio of these two parameters exceeds a certain limit. In addition, to reduce the risk of piping formation, the allowable seepage discharge is not more than 1% of the annual average discharge of water entering the dam. Based on these conditions, this research discussed on related matters namely seepage discharge and piping safety factor at downstream-toe side of the dam in condition of both with and without foundation improvement. The Geostudio Seep/W software was used as an analysis tool based on design of Way Sekampung Dam. Several cases of simulations have been identified based on the combination of typical cross-sections and different foundation improvement methods (curtain grouting and upstream blanket). The result of the analysis has exhibit that all cases have met the requirements of seepage discharge and piping safety factors.