GEOTECHNICAL PROPERTIES OF LATERITIC SOILS FROM DAMATURU AND POTISKUM LOCAL GOVERNMENT AREA

Lateritic soils are commonly used as construction materials for road pavements in tropical regions such as Nigeria due to their widespread availability and cost-effectiveness. However, the engineering behavior of lateritic soils varies significantly depending on their particle size distribution, plasticity characteristics, moisture content, and degree of compaction. This study evaluates the geotechnical properties of lateritic soils obtained from selected locations within Damaturu and Potiskum Local Government Areas of Yobe State with the aim of assessing their suitability for road construction and related civil engineering works.Four lateritic soil samples were collected from Damaturu–Gujuba Road, Adaya Damaturu Road, Gashua Road Damaturu, and Potiskum–Gashua Road (Kanda). Laboratory tests including sieve (particle size) analysis, Atterberg limits tests, compaction tests, and California Bearing Ratio (CBR) tests were carried out in accordance with relevant British Standard procedures. The sieve analysis results indicated that all soil samples are predominantly coarse-grained with fines content ranging from 6.1% to 8.7%, which is characteristic of lateritic soils. The Atterberg limits results showed liquid limit values ranging between 22% and 42% and plasticity index values between 10.6% and 18.7%, classifying the soils as low to moderately plastic.The compaction test results revealed maximum dry density values ranging from 2.175 g/cm³ to 2.545 g/cm³ at optimum moisture contents between 6.4% and 12.1%, indicating good compaction characteristics. The California Bearing Ratio results showed significant variation in strength among the soils, with values ranging from 3.1% to 92.8%. The soil sample from Damaturu–Gujuba Road exhibited excellent bearing capacity and is suitable for use as base and sub-base material, while the soil from Gashua Road Damaturu recorded very low CBR values and requires stabilization before use in pavement construction.The study concludes that most lateritic soils within the study area possess satisfactory engineering properties for use as subgrade and sub-base materials when properly compacted and provided with adequate drainage. However, soils with poor bearing capacity should be improved through appropriate stabilization techniques to ensure satisfactory field performance. The findings of this study provide useful guidance for engineers involved in pavement design and construction within Damaturu and Potiskum Local Government Areas.