Dynamic response analysis of Talcher pond ash embankment in India

This paper presents the dynamic response analysis of Talcher pond ash embankment in India, considering both full saturation and existing water table condition subjected to earthquake excitation. Static and cyclic triaxial tests were performed to determine the parameters required for the dynamic response analysis of the existing pond ash embankment. From the cyclic triaxial test, it is observed that Talcher pond ash is susceptible to liquefaction. A two dimensional nonlinear finite element analysis using Open System for earthquake engineering simulation (OpenSees) has been carried out to study the dynamic response analysis of the existing embankment. The pre and postprocessing phases have been done using GiD 7.2 software. The North East India earthquake, May 08, 1997 (Motion 1) and North East India earthquake, Aug 06, 1988 (Motion 2) have been used as the input motion for the dynamic response analysis. The model has been validated with the results of cyclic triaxial test performed on Talcher pond ash. From analysis, it is observed that under full saturation condition, the maximum horizontal and vertical displacement below the slope of the embankment is 4.505 m and 3.247 m respectively. Also the pore pressure ratio below the slope is observed more than unity. The pond ash embankment is not safe against liquefaction and lateral spreading under full saturation condition. However, under existing water table condition the embankment is safe against liquefaction.