COMPARATIVE ANALYSIS OF NEW AND USED TYRES: TYRE LIFE, TREAD DEPTH, AND ENVIRONMENTAL IMPACT

Comparative analysis of new and fairly used tyres is important for evaluating their performance, safety, cost-effectiveness, and environmental impact and to undertake research and development in tyre technology. This study presents a comparative analysis of new and used tyres, focusing on their lifespan, tread depth, and environmental impact. Mathematical models were developed to predict tyre lifespan and environmental impact. Experimental tests were also conducted on several tyre brands available in Nigeria to assess changes in hardness, tensile strength, and impact strength over time. The average values of hardness obtained during the hardness tests for the new tyres for samples A, B, C, D, and E are 66, 70, 68, 60, and 76 and for the fairly used tyres of the same samples for 1, 2, 3, 4, 5, and 6 years are 79.5, 77, 71.7, 69.2, and 80 respectively. The tensile stresses also obtained range from 7.80 to 8.20 N/mm2. The stresses obtained at 100% and 200% range from 2.77-2.83 N/ mm2 and 5.90 – 5.99 N/mm2, respectively. The strain at break was within 233 to 247%. Results show a decline in the mechanical properties with increased usage, and the models suggest that the tread depth significantly influences the performance, safety, and fuel efficiency