AN EXPERIMENTAL STUDY ON UTILIZING BIOENZYME FROM FERMENTED ORANGE PEEL ( CITRUS RETICULATA ) WASTE AS REPLACEMENT FOR STABILIZERS FOR SOFT SOIL IN ROAD PAVEMENTS

Abstract

Road transportation plays a pivotal role in every civilization and nation. Soft soil is a primary contributor to pavement failures due to its inability to maintain its original shape and develops stress along its physical and geotechnical characteristics. In hindsight, various soil stabilizers have emerged in civil engineering, including the utilization of bioenzymes. The study investigated the effectiveness of varying dosages of bioenzyme from fermented orange peel (Citrus reticulata) waste as soil stabilizer in a seven (7-day) curing period. The potential of hydrogen (pH) meter, biochemical oxygen demand (BOD), and chemical oxygen demand (COD) content through a titrimetric method and a closed reflux method characterized the waste of fermented orange peel (Citrus reticulata) . The obtained data were analyzed and investigated in terms of consistency, compaction, California bearing ratio (CBR), and swelling. The result demonstrates that 20 mL/50 kg of bioenzyme is the optimum dosage for the selected soft soil for maximum dry density (MDD) and swelling. In contrast, the 25 mL/50 kg dosage of bioenzyme has shown minimal improvements on the selected soft soil in terms of optimum moisture content (OMC) and plasticity characteristics. The present study concludes that the overall results have shown nominal improvements, yet it needs to conform to the standard subgrade requirement for road pavements. Moreover, further examination of the effects of bioenzyme in various curing days and the use of higher dosages may also help in utilizing the soil to conform to the standard subgrade requirement.