Stability Analysis of Slope Induced with Coal Ash Dykes

Abstract

Safe disposal of coal ash slurry is a primary concern of the environment owing to the bulk generation of ash in industries, especially in any developing country. Generally, it is observed that the generated coal ash waste is disposed of into the ash ponds as slurry. Ash dyke breaches may inundate the surrounding area with toxic ash slurry, thus inducing a high environmental hazard. This article presents a study on the slope stability of ash dyke structures for different geometries, which may be constructed of various materials and are subjected to varied seepage conditions. The present analysis compares different dyke erection methodologies, namely the upstream method, centreline method and downstream method. Numerical analysis is performed using Geostudio Slope/w software. The study found that ash dyke safety increases when the dyke structures are designed with adequate drainage. Further, from this study, it can be concluded that the dyke stability not only depends on the geotechnical properties of the ash material used in its construction but also on the design of the dyke, the method of erection and the seepage through the dyke.