Assessment of the Geotechnical Properties of Termite Mound Soils from Selected Communities in Edo and Delta States, Nigeria

Abstract

Termite mound soils are naturally modified through particle transport, clay enrichment, and biochemical binding processes, which can influence their physical and mechanical properties. Evaluating these soils is important for determining their potential suitability as locally available materials for selected geotechnical applications. This study assessed the geotechnical properties of termite mound soils and their potential use as locally available engineering materials. Soil samples were collected from seven communities in Edo and Delta States, Nigeria, composited by location, air-dried, prepared, and subjected to laboratory testing. The evaluated parameters included liquid limit, plastic limit, plasticity index, linear shrinkage, maximum dry density, optimum moisture content, cohesion, angle of internal friction, and specific gravity. Liquid-limit values ranged from 32% at Ologbo to 52% at Obanyantor, while plastic-limit values ranged from 15.1% to 25.3%. The plasticity index varied from 16.9% to 26.7%, indicating medium to high plasticity. Linear shrinkage ranged from 8% to 12%. Maximum dry density ranged from 1.61 to 1.82 Mg/m³, and optimum moisture content ranged from 15.0% to 20.5%. Cohesion values ranged from 54 to 77 kN/m², while the angle of internal friction ranged from 18° to 23°. Specific gravity ranged from 2.43 to 2.86. These results indicate that the sampled termite mound soils have moderate compaction and shear-strength characteristics, although their properties vary among locations. The soils may therefore have potential for selected geotechnical applications or as soil-improvement materials. However, additional engineering tests and field-performance evaluations are required before their direct use in construction can be recommended.