Comprehensive feasibility study for application of waste tire chips in enhancing the performance of shallow foundations

This study aims to assess the viability of waste tire chips as sand reinforcement for enhancing the performance of shallow foundations. Detailed experimental investigation is carried out to analyze the behavior of model footing placed on sand reinforced with waste tire chips, and the observed improvement is quantified in terms of a non-dimensional factor, bearing capacity ratio (BCR). The influence of variation of several factors such as the content of tire-chip reinforcement, the extent of tire reinforced sand zone, footing shape, the effect of submergence, and scale effects on BCR has also been studied. Test results indicate significant improvement in BCR validating the effectiveness of tire chips in improving the bearing capacity of sand. The optimum tire content, depth of reinforced zone, and width of the reinforced zone are recommended as 30%, 1B-2B, and 3B-5B, respectively (B is the width of the footing), where BCR increased to more than 5 under both low strain and high strain conditions. It was also established that submergence of the reinforced soil and shape and size of footing did not have a significant influence on the BCR. Moreover, the performance of tire chip-reinforced sand is found to be better than both fiber- and geogrid-reinforced sand. Bearing capacity increase of up to 1.89 times and 2.40 times was observed in tire chip-reinforced sand in comparison to fiber- and geogrid-reinforced sand, respectively. On the whole, the significant improvement in BCR and the better performance of tire chips over other alternatives ascertain that bulk utilization of tire wastes in shallow foundations has immense potential for effective waste management of large stockpiles of tires and can prove to be an economical and sustainable solution for the construction industry.