In recent years, new dangers to coastal areas have emerged as a consequence of climate change and rising sea levels. This necessitated a need for developing alternative shore protection measures. Anchored geosynthetic systems (AGS) were evolved as a technique for stabilizing slopes at or near failure state as well as erosion control. This paper evaluates influence of the AGS system on stability and performance of a 12 m high silty sand slope subjected to seepage by using centrifuge modeling technique. Seepage condition was simulated using a seepage flow simulator causing to rise in phreatic surface level at 50g. In this paper, results of two centrifuge tests carried-out on 1V:1H slopes are presented to bring-out the efficacy of AGS system in ensuring slope stability and improving the performance during centrifuge tests. Based on scaling relationships, anchors and geosynthetics were scaled-down and were modeled as pre-tensioned anchors and a geocomposite layer, respectively. An anchor inclination of 15° with the horizontal was adopted for AGS slope model. Nine numbers of anchors were spaced in a square grid of 3 m centre to centre both in horizontal and vertical direction on the slope surface. Both the centrifuge models were instrumented with linearly variable differential transformers (LVDTs) and pore water pressure transducers (PPTs) to measure surface displacements from crest of the slope and development of phreatic surfaces within the slope. Digital image analysis technique was employed to trace the movement of plastic markers embedded within the slope body as well along the slope face at the onset of seepage. In addition to substantial effect of employing AGS on slope stability, ability of centrifuge modeling in rendering reasonable results, concerning AGS slopes under seepage condition are addressed.
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