Toward the development of sustainable concrete with Crumb Rubber: Design-oriented Models, Life-Cycle-Assessment and a site application

This study shows a comprehensive research program and practical application of concrete made from crumb rubber produced using end-of-life tyre for use in municipal concrete infrastructure. In light of a large experimental database containing 1334 datasets reported in 126 studies and covering a wide range of parameters, design-oriented models for the compressive strength of crumb rubber aggregate based concrete (CRC) is developed and a large scale life-cycle analysis (LCA) is undertaken to theoretically assess the mechanical properties and environmental performance of concrete containing crumb rubber aggregates. Using the developed models for the compressive strength of CRC and the established LCA, the allowable crumb rubber content in concrete to maintain the sustainability and mechanical properties of the concrete can be identified. Following the theoretical work, a lab-based experimental program is conducted to develop a green concrete mix containing crumb rubber aggregate and other waste-based materials including ground-granulated blast-furnace slag, manufactured sand and recycled PET fines to meet the practical and commercial requirements, field applications of these concrete as pavement materials. Finally, a site application of the developed green concrete is performed to demonstrate that the innovative “green” premix concrete has appropriate engineering properties to enable its use in concrete applications for municipal concrete infrastructure. The benefits and outcomes of this work for the concrete construction are to allow:1) an alternative to recycle end-of-life tyres, 2) for more rapid development of green concrete using waste-based materials for construction applications with high confidences and 3) a faster transition of the materials from lab technologies to real-world engineering applications.