Effects of scrap tyre rubber fibre on swelling behaviour of two clayey soils in Algeria

Abstract

ABSTRACT: An experimental programme was undertaken to investigate the effect of scrap tyre rubber on the swelling behaviour of composite clayey soils, using a large mix ratio. Two soils were studied (Ayaida and bentonite soils in the north-west of Algeria) by considering the high compressibility and low water absorption of scrap tyre rubber. Grain size, specific gravity, Atterberg limit analysis, swell-consolidation and loading–unloading tests were performed on the two soils and their mixtures with varying fibre content (10%, 20%, 25% and 50%). The results show that the liquid limits, swell potentials, swelling pressure and time to reach maximum heave decrease gradually when the scrap rubber content increases, and this reduction is significant for the soil with the higher swelling potential. Owing to the high compressibility of scrap tyre rubber, the compression and recompression indexes increase considerably with the content of scrap tyre rubber. It appears from the results that scrap tyre rubber can be used as reinforcement material for the modification of clayey soils, yet with a content that should not greatly affect the mixture compressibility.