This research investigated the possibility of using Calcium carbide residue (CCR) as an additive in the modification of the geotechnical properties of clay soil from Ameki formation in Ozuitem so as to increase their strength bearing capacity and reduce their swelling potentials. The clay soil samples were collected from Ozuitem LGA of Abia State. Chemical analysis of the CCR shows that it contains 65.71%, 27.93% and 4.01% of CaO, Ag2O and SiO2 respectively. Preliminary tests to determine the geotechnical properties of the natural soil including Particle size distribution, Atterberg limits, Maximum Dry Density and California Bearing Ratio were determined in the laboratory to classify the soil. The soil samples were later stabilized with various percentages of CCR (2, 4, 6, 8 and 10). The geotechnical tests earlier performed on the soils were repeated (after stabilization) to evaluate the effects of CCR on the geotechnical properties of the clay soils. Results of the study indicate that CCR stabilization of clay soils in Ozuitem has the general effect of reducing the swelling indicators, thereby reducing the swelling potential of the soil. The liquid limit ranges between 31.51% to 43.18% and plasticity index extends from 12.14% to 23.005%. Optimum stabilization was achieved with 8% CHA stabilization. Stabilization with CCR acts like lime stabilization by increasing the CBR but reducing the MDD of the soils. Therefore, calcium carbide residue can be effectively used to reduce swelling indicators and to improve CBR values in clay soil and should be encouraged in the construction industry
Michael Chukwuma Eze (Fri,) studied this question.