EVALUATION OF SHEAR STRENGTH OF COMPACTED IRON ORE TAILINGS TREATED LATERITIC SOIL

Abstract

This paper presents the results of a laboratory study on the evaluation of the shear strength of compacted iron ore tailings (IOT) treated lateritic soil. Lateritic soil used was treated with 0 up to 16% IOT by weight of dry soil. Test performed include index test, compaction (using British Standard Light, BSL and West Africa Standard, WAS energies) and shear strength test. One-way analysis of variance was carried out using Microsoft Excel to determine the level of significance of IOT on the treated soil. The results of the triaxial test show that there is an improvement in the shear strength of soil with the improvement of its shear strength parameters (cohesion and angle of internal friction). Cohesion values decreased from 0 up to 8% IOT content and then increased while the angle of internal friction risen from 0 up to 8% IOT content and then decreased. Also, from the triaxial test carried out with varying cell pressures from 100 to 300 kN/m2, an increase in shear strength parameters and shear strength were recorded. The shear strength increased in value by 49.79% and 18.15% for BSL and WAS compaction at 8% IOT content, respectively. Statistical analysis carried out on the results using analysis of variance (ANOVA) shows that IOT has a significant effect on the lateritic soil. An optimal blend of 8% IOT improved the shear strength of the soil and can be used for geotechnical engineering applications such as roads and embankments.

Keywords

• angle of internal friction
• cohesion
• iron ore tailing contents (iot)
• lateritic soil and shear strength