Investigation of Cracking Potential Using Dewatered Sludge as Landfill Liner

Many studies have investigated dewatered sludge utilization as a landfill liner. The main reason for this utilization is because of the dewatered sludge’s strength and hydraulic performance, the discovery found. Cracks influence hydraulic properties; cracks’ existence causes a sharp rise in water conductivity, compromising the barrier system. There is considerable research on dewatered sludge as a landfill liner, but few prioritize crack as the main factor. This study analyzes the dewatered sludge’s cracking potential as a landfill liner by testing swelling bentonite, proctor standard, permeability, and desiccation with WD cycle methods. Results show each composite free swell index consisting of dewatered sludge, bentonite, and tire fiber is influenced massively by different materials. Bentonite can alter the dewatered sludge’s plasticity characteristics, making the composite more plastic and increasing its plastic index from 5 to 15%. Five variants’ OMC and MDD values showed no appreciable difference ranging from 25–42% and 1.3–1.37 gr/cm3. Based on its density value of 1.22 gr/cm3, permeability of 3.72 × 10–7 cm/s, and CIF value of 0.9538%, which satisfies the standards for the value of depreciation, V2 with 75% dewatered sludge, 10% bentonite, and 15% tire fiber, is the best option for a landfill liner.