Open Collections

Injamala, Sharon Kumar

University of British Columbia

Desiccation cracks in landfill liners pose several problems that can significantly impact the performance and environmental safety of landfills. This study presents two different sustainable stabilizing materials to minimize the cracking properties and improve the geotechnical properties of bentonite for its application in landfill liner systems. One of those sustainable stabilizing materials is biochar which has been widely used to improve soil quality and store atmospheric carbon dioxide. The other material is a biopolymer which helps in the polymerization of clays and has gained significant interest due to its sustainability characteristics. Three different percentages of biochar (5%, 15%, 25%) of sizes less than 0.075 mm and three different percentages of biopolymer (0%, 2%, 4%) are mixed with bentonite clay followed by investigating their volumetric shrinkage behavior, compaction and compressive strength characteristics. The desiccation cracking is assessed with the help of ImageJ analysis in terms of Crack Intensity Factor (CIF) and Crack Density Factor (CDF). The microstructure analysis using a Scanning electron microscope (SEM) is carried out to visualize how the composite materials interact when mixed. Finally, the adsorption studies are conducted to determine the effect of biochar and biopolymer on the adsorption behavior of bentonite using Lead (Pb²⁺) as a contaminant. The compaction and compressive strength values are highest at biochar (5%) and biopolymer (4%). Furthermore, the biochar-amended bentonite displayed improved adsorption behavior, volumetric shrinkage and crack resistance in terms of CDF and CIF. The results indicate that biochar and biopolymer are sustainable amendments to the high-swelling bentonite clay to improve its geotechnical properties for its application as a landfill liner material.

Text

2025-04-30

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/88320

Civil Engineering

University of British Columbia

UBCO

http://creativecommons.org/licenses/by-nc-nd/4.0/