Abstract
Water treatment sludge (WTS) has in recent years been used for improvement in geotechnical properties of soil. The present study has been taken up to establish whether WTS can be used for the improvement of gypseous soil by assessing its effects on the geotechnical properties. Soil samples were collected from the study area while WTS were locally obtained from a water treatment plant. Chemical and physical properties, mineral compositions, particle size distribution, water content, and Atterberg limits of soil and WTS were determined. The laboratory test was performed by employing laboratory testing to investigate the effects of different percentages of WTS on the strength, compressibility, collapsibility, and compatibility of the soil at different curing times. The results obtained showed that WTS influenced the geotechnical properties of gypseous soils significantly. Improvements in the strength, compressibility, and collapsibility were shown. The best application rate of WTS was suggested on the basis of the possible improvements in the geotechnical properties. From the study’s outcomes, it could be concluded that the use of WTS may be an alternate and economic material for the improvement of geotechnical properties of gypseous soil.