Compactoin And Ompaction And Shear Strength Of Fly And Bottom Ash Mixtures

Bottom ash and Class F fly ash are by-products of energy generation in coal power plants. A large fraction of the coal ash generated is disposed as a waste material in the form of mixtures. Bottom ash and Class F fly ash could be more productively used as construction material for embankments and structural fills. For this reason, their engineering behavior needs to be investigated, particularly their compaction properties and shear strength. Representative, large ash samples were collected from a power plant in Indiana. The bottom ash was sampled from a pond, and the Class F fly was sampled from a silo. Samples of mixtures with different proportions of fly to bottom ash were composed and tested in compaction following the Standard Proctor Test procedure. To investigate stress-strain behavior, consolidated drained triaxial compression tests were performed on samples of mixtures compacted at two levels of relative compaction. The investigation focused on the effects of the fly ash content and the compaction level on the mechanical behavior of the mixtures. The application of the results to compaction control and construction of embankments is also discussed.