The growing global issue of waste tyres, which are non-biodegradable, poses serious environmental risks, with improper disposal and burning contributing to air and water pollution through the release of harmful chemicals and greenhouse gases. However, waste tyres possess unique engineering properties such as high tensile strength, permeability, durability, fatigue resistance, resilience, and flexibility. This study explores the potential of utilizing waste tyres to enhance soil strength through experimental investigations. Laboratory model tests were conducted on circular footing (150 mm diameter) placed on various foundation systems, considering sand or sand-tyre shred mattress overlying a soft clay bed (Cu = 14.5 kPa), with and without geogrid reinforcement at the interface of soft clay and sand-tyre. Results revealed that the maximum improvement in bearing capacity of the foundation systems, with or without geogrid, was observed at a thickness of sand layer (hs) or sand-tyre mixture (hSTM) = 1.5D, over the soft clay. Results also revealed that with the inclusion of tyre shreds (7.5% by volume) with sand, over the soft clay bed, the bearing pressure of foundation system S-IV increased by 200.01% (at hsTM = 1.5D) in comparison with S-I. This improvement in bearing capacity of S-IV (i.e. clay + sand + tyre) was 3.5 times than S-I, which is similar to the improvement in bearing capacity of foundation system S-III (i.e. clay + geogrid + sand). Based on the experimental evidence, it can be suggested that the application of tyre shred is beneficial in geotechnical engineering practices to improve the performance of soft clay foundation systems.

来源平台：INDIAN GEOTECHNICAL JOURNAL