PERMEABILITY AND CONSOLIDATION CHARACTERISTICS OF COMPACTED FLY ASH

Abstract

Thermal power stations use pulverized coal as fuel. They produce enormous quantities of coal ash as a by-product of combustion. This calls for the development of strategies to encourage and establish technological concepts which will ensure consumption of fly ash in bulk. Detailed testing regarding geotechnical utilization was carried out on fly ash from the Dadri Thermal Power Station, Ghaziabad (Uttar Pradesh). The chemical composition and physical properties of the fly ash were determined. The morphology of the fly ash particles was studied by scanning electron microscopy. An X-ray diffraction test was also conducted for phase composition. The geotechnical testing program included the classification tests, the compaction test, the consolidation test, and the permeability test. The paper explains the details and results of the tests, especially those of the consolidation and permeability behaviors. The consolidation and permeability characteristics of the Dadri fly ash have been compared with those of some other Indian fly ashes. This paper presents a review of some of the experimental studies carried out in the laboratory. The purpose is to find out a suitable utilization avenue for a particular fly ash sample depending upon its physical, chemical, morphological and engineering properties and thus reduce the need for vast areas for disposal of fly ash which in turn causes considerable damage to the environment. Some of the experiments which are conducted are particle size analysis, specific gravity, X-ray diffraction (XRD) studies, and Scanning Electron Microscopy (SEM) studies. Based on the results obtained from these experiments, suitable end use for the fly ash based on the characteristics of the samples is ascertained.