Studies on Performance Characteristics of Bituminous Mix Using Proteinous and Non-Proteinous Wastes of Leather

The leather industry generates a significant amount of solid waste during the processing of animal hides and skins, including proteinous wastes like chrome shavings and fleshing residues, as well as non-proteinous wastes such as buffing dust. Improper disposal of these wastes poses serious environmental challenges due to their chemical composition, particularly the presence of chromium. This study investigates the feasibility of utilizing these leather industry wastes in the construction of Stone Matrix Asphalt (SMA) pavement layers. In this research, lime obtained from limed fleshing was used as a filler, and chrome shavings were employed as a stabilizing additive in SMA mixtures. The mix designs were prepared in accordance with IRC: SP-79-2008 specifications and tested using the Marshall Method to determine the optimum binder content. Performance evaluation was carried out through various laboratory tests, including Marshall Stability, Indirect Tensile Strength (ITS), Moisture Susceptibility, and Wheel Tracking (Rutting) tests. The results indicated that the modified SMA mixes exhibited enhanced mechanical properties, including improved stability, moisture resistance, and rutting performance, while also meeting all specified standards. Furthermore, the reuse of leather waste materials contributes to sustainable construction practices and offers an environmentally responsible solution for waste management in the leather industry. This study concludes that incorporating leather waste in bituminous mixes is both technically viable and environmentally beneficial, paving the way for eco-friendly and cost-effective road construction solutions.