Pullout behaviour of polymeric strips embedded in mixed recycled aggregate (MRA) from construction & demolition (C&D) waste – Effect of type of fill and compaction

Abstract

Recycling and reusing construction and demolition (C&D) waste is the pressing priority, and the use of such non – conventional structural fill in reinforced soil structures (RSS) is gaining momentum. However, the utilisation of mixed recycled aggregate (MRA) from processed C&D waste as structural fill with polymeric strips (PS) and the effect of poorly compacted structural fill on the pullout interaction is not reported. This research presents the viability of using MRA as a structural fill for reinforced soil structures, appraising the physical, mechanical and electrochemical properties of MRA and the pullout behaviour of polymeric strips embedded in MRA at different relative densities in a large-scale pullout box. The results for MRA were compared with those obtained using locally available coarse and fine sands. The test results showed that MRA was alkaline (pH < 9) and had good mechanical properties and shear strength suitable for reinforced soil structures. Pullout testing results exhibited high values of the interface apparent coefficient of friction (μS/GSY) under dense conditions and a 70–80% reduction in loose conditions. The present study reinforces the viability of using MRA as an alternative structural fill with PS and highlights the effect of construction variability on μS/GSY.