Recycling rubber waste for geotechnical applications: preliminary results on compressive response

Every year tonnes of rubber wastes are generated as a byproduct of human activities, including end-of-life tires and industrial byproducts. Managing these wastes has become a global concern, therefore, alternatives for their valorisation are being sought. Among these alternatives, geotechnical engineering offers a promising route for large-volume reuse of this material, transforming a problematic waste into a valuable resource for constructing civil infrastructure. Potential geotechnical applications include the use of rubber waste in various forms (e.g., crumbs, fibres, mats) as lightweight fill materials in embankments and foundations, vibration damping layers in railway subgrades, and in seismic isolation systems. However, their valorisation raises concerns regarding the risk of contamination of soil or groundwater. Their deformability and compressibility behaviour, namely when included within unbound aggregate-rubber mixtures can also be challenging. This work presents preliminary results on the physical characterisation and assessment of one-dimensional (1D) compressive response of crumb rubber. The ultimate goal is to assess the potential of this end-of-life tire waste to be included within unbound aggregate matrices. The characterisation included particle size distribution, specific gravity, estimation of the internal friction angle and oedometer and 1D compressive creep tests. The findings provide initial insights into the fundamental compressive behaviour of the selected rubber waste, supporting its potential valorisation in geotechnical applications aligned with sustainability and circular economy principles.