Seismic Response Analysis of Renusagar Pond Ash Embankment in Northern India: Fid-Bau Portal

Seismic Response Analysis of Renusagar Pond Ash Embankment in Northern India

Vijayasri, Thanikella / Raychowdhury, Prishati / Patra, Nihar Ranjan

Utilization of fly ash as a suitable and economic alternative to natural soil for construction of embankments is becoming common, particularly in countries such as India, where thermal power plants are still a major source of power. However, while using this material in a seismic zone, its dynamic properties may play a crucial role during an earthquake event. Of particular concern is the vulnerability of the material to liquefaction-induced failure, because pond ash mainly consists of noncohesive fine sand and silt. The present work focuses on dynamic response analysis of a 52-m-high pond ash embankment situated in Renusagar, northern India, using a fully coupled nonlinear finite-element analysis. Constitutive material models of the pond ash material were calibrated using cyclic triaxial experiment data performed on pond ash samples collected from the aforementioned embankment. A significant amplification in the acceleration response was observed between the base and crest of the embankment ranging from 1.43 to 4.2 (mean, 2.9). The mean amplification profile is consistent with the observation from the literature. A large amplification in the horizontal as well as vertical displacement is also observed with values up to 17.3 and 45 cm, respectively. The pond ash embankment is found to be susceptible to liquefaction for the majority of the earthquake motions considered in the study.