Investigation of the usability of Trabzon region drinking water treatment plant sludge in soil stabilization

In this study, the usability of sludge obtained from drinking water treatment plants in the stabilization of clayey soils was investigated. In this context, the physical, mechanical, chemical, and mineralogical properties of sludge samples obtained from the Esiroğlu (AÇ-1), Derecik (AÇ-2), and Akçaabat (AÇ-3) drinking water treatment plants (İSATAÇ) located in different regions of Trabzon province were determined. As a result of the conducted studies, the sludge from the Esiroğlu Drinking Water Treatment Plant (AÇ-1) exhibited more favorable engineering properties for soil stabilization compared to the other sludge samples. Accordingly, instead of the initially determined waste ratios of 0%, 5%, 10%, 20%, 30%, and 50%, the most effective waste ratios of 0%, 10%, 30%, and 50% were selected for further advanced experiments in terms of efficient material utilization. The samples prepared at the determined additive ratios were subjected to curing for periods of 0, 7, 15, 30, 60, and 360 days; additionally, tests were conducted for 0, 1, 3, 5, 7, and 11 cycles to evaluate freezethaw resistance. After these procedures, the microstructural changes in the samples were examined in detail using SEM (Scanning Electron Microscopy) and XRF analyses. The findings revealed that the sludge from the Esiroğlu treatment plant, in particular, can be considered an effective additive material in improving the performance of soils to be stabilized.