A Study of Water Permeability of Coal Ash and Slag to Assess the Possibility of Their Use as Road Pavement Layers

Abstract

This paper focuses on problem of the coal combustion waste use. The possibility of using the coal ash and slug as an additional layer of road pavement is considered. Particular attention is paid to water permeability, which along with the mechanical properties determines the possibility of their use as pavement layers. A series of laboratory studies on samples from the two ash dumps were conducted. This made it possible to determine the values of permeability coefficient for various types of waste having different densities. The research was conducted in laboratory on the equipment that allowed us to change the value of hydraulic gradient (for individual experiments). It was found that filtration begins only when the initial filtration gradients are exceeded, which is associated with the features of composition and structure of coal ash and slug. These results can be used to make a final decision on feasibility of using the coal waste as a layer of road pavement.

Measurements of the Permeability Coefficient of Waste Coal Ash under Hydrostatic Pressure to Identify the Feasibility of Its Use in Construction

“…Recycling 2024, 9, x FOR PEER REVIEW 3 of 15 al. in order to assess the possibility of their use as road surface layers [19]. Ash samples collected from two landfills with different densities were tested in an extremely dense and loose state.…”

“…This effect was related to the features of the composition and structure of the coal residue. The works available in the literature mainly concern the permeability coefficient of coal fly ash, while those concerning bottom ash are very rare [17,19,21,22]. The aim of this work was to measure the filtration properties of waste coal ash samples with a different density index and to discuss the impact of hydrostatic pressure on the value of the permeability coefficient.…”

“…Research on the assessment of the permeability coefficient of waste coal ash is limited [17][18][19][20]. The water permeability of coal ash and slag was studied in the work of Lange et al in order to assess the possibility of their use as road surface layers [19]. Ash samples collected from two landfills with different densities were tested in an extremely dense and loose state.…”

“…This effect was related to the features of the composition and structure of the coal residue. The works available in the literature mainly concern the permeability coefficient of coal fly ash, while those concerning bottom ash are very rare [17,19,21,22].…”

Management of groundwater resources in transboundary territories (on the example of the Russian Federation and the Republic of Estonia)

“…Since the Lomonosov aquifer is isolated by aquicludes, is unlimited in plan and is a pressure head, the Theis scheme is used to calculate the depression [22,23]. On the territory of work, water intakes will be considered as compact groups of wells, therefore, it is advisable to calculate using the "big well" method.…”