Design of Core of Earthen Dam by Replacement with Geosynthetics

Earthen dams are embankments constructed from easily available soil in the vicinity of the construction site. The main components of an earthen dam are outer shells and inner core. The core is provided in the center of the dam to reduce the seepage through the embankment. The core materials of earth dams are usually selected based on available burrow areas and mainly from low permeable geomaterials (mostly clay). Many times, it may be difficult to find a suitable clay for the core in the locality of the embankment. In the present study, the effect of the introduction of Geosynthetic Clay Liner (GCL) in the core of the embankment is analyzed. A 33 m high embankment was considered and analyzed for seepage and slope stability analysis. In the present study, a geosynthetic clay liner is introduced in the core in order to reduce the thickness of the clay core. Seepage flow analysis through the embankment is studied with and without a Geosynthetic Clay Liner. Steady and sudden drawdown conditions are also considered in the study. It is observed that the usage of Geosynthetic Clay Liner results in the reduction of seepage flow through the embankment by 22%. Even the core material has been reduced by 13%.