Effect of Addition of Carpet Waste Fibres on the Unconfined Compressive Strength of Cohesive Soils Samples from Umutu, Agbor and Obiaruku in Delta State, Nigeria

With the latest trend in the beautification of most homes and offices, there has been a great shift from the use of carpets to floor tile and as such most of these carpets have become waste and causing environmental pollution. Therefore the objective of this paper was to evaluate the effect of adding carpet waste fibre on unconfined comprehensive strength of cohesive soil samples from Umutu, Agbor and Obiaruku in Delta State, Nigeria using standard techniques. The results showed that the maximum dry  density (MDD) of the natural soil samples from Umutu, Agbor and Obiaruku  were 1.76g/cm3, 1.73 g/cm3 and 1.72 g/cm3 respectively while their respective OMC were 13.6%, 13.86% and 14.2%. The UCS of the natural soil samples were 68.6kN/m2, 73.77kN/m2 and 76.69kN/m2 respectively. The MDD decreased from 1.73 g/cm3 to 1.675g/cm3, 1.72g/cm3 to 1.66g/cm3 and 1.71 g/cm3 to 1.63 g/cm3 when the natural soils from these study areas respectively were compacted with 0.1% to 0.4% fibre content. Also, the OMC from the respective soils-fibre mix increased from 13.8% to 19.0%, 16.0% to 19.6% and 14.9% to 19.2% respectively. The UCS for the respective soil-fibre mix decreased from 60.38kN/m2 to 52.65kN/m2, 66.28kN/m2 to 57.70kN/m2 and72.39kN/m2 to 57.27kN/m2. Hence, the study showed that the addition of fibre to natural soil decreases the strength of the soil