Behaviour of fly ash-lime-gypsum composite mixed with treated tire chips

The present study is carried out to investigate the strength behaviour of the reference mix containing fly ash + 8% lime + 0.9% gypsum mixed with treated tire chips. The dry tire chip was treated with water, sodium hydroxide and carbon tetrachloride. The tire chip content in the reference mix was varied from 5% to 15% and curing period from 7 days to 180 days. The specimens were cured using three different methods of curing (in a dessicator, burlap and water filled container). The results of this study reveal that the stress - strain relationship, strength characteristics, initial tangent modulus, ultimate strength and secant modulus of the reference mix containing dry tire chips is influenced by the tire chip content, curing period, curing method and the treatment provided on the tire chips. These parameters increased with the treatment provided with water, sodium hydroxide, carbon tetra chloride as well as with the increase in curing period in comparison to dry tire chips in the reference mix. A higher increase in these parameters was observed when specimens were cured in water filled container followed by burlap and dessicator respectively. Study further revealed that these parameters decreased with the increase in tire chip content from 5% to 15% and increased with the increase in the confining pressure. The axial strain at failure increased with the treatment provided with water, sodium hydroxide and carbon tetra chloride in comparison to dry tire chips in the reference mix. The results further revealed that axial strain at failure increased with the increase in curing period, change in curing method and increase in confining pressure. Inclusion of 5% dry/treated tire chips in the reference mix increases the axial strain at failure. Beyond a tire chip content of 5%, the axial strain at failure decreased when the content of tire chip was increased to 10% and 15% respectively.