Evaluating the Utility of Pond Ash as an Alternative Foundation Material Partially Replacing Sand for Foundation Layers

Abstract

AbstractThe target of cent-percent utilization of the coal combustion ash likely to be generated in India in the upcoming years is definitely going to be a daunting task with its disquieting production and defined usage. Moreover, the harmful environmental and human health impact of the coal combustion ash stored in ash lagoons (Pond Ash) is demanding some immediate step for its effective bulk usage in a more eco-friendly way. The Supreme Court of India’s order of imposing regulation on unconstrained fine aggregate excavation have turned the attention of the researchers toward Pond Ash (PA) and its potential usage as partial replacement of the Conventional Granular Material (CGM) for foundation layers. In this investigation the samples of PA were collected from Kolaghat Thermal Power Station (KTPS) ash pond in India and tested for its engineering properties (Specific gravity, Compaction behavior, Hydraulic conductivity, and Shear strength) along with gradation. Five mixtures of PA and zone-III sand with different mixture ratios (3, 6, 9, 12 and 15% PA content by weight of zone-III sand) were prepared for testing. Mineralogical analysis (XRD and FTIR) of the Virgin PA sample was conducted for verifying the pozzolanic nature of the collected PA sample. The test results showed favorable comparison of ash with the conventional granular material and PA is a promising Non-Conventional Granular Material (NCGM) which can be used effectively as well as economically by the industries as a foundation layer material, which will also address its disposal problems.KeywordsPond ashChemical compositionEngineering propertiesXRDFTIR