DETERMINING THE SUITABILITY OF CLAY AT ITU, AKWA IBOM STATE, NIGERIA FOR ROAD CONSTRUCTION

Abstract

Incessant road failures in Nigeria have become an issue of serious concern in recent times as a large portion of states and federal budgets are dedicated to revamping road infrastructures. In this study, we examined the geotechnical properties of clay samples collected from Ntak Inyang along Calabar-Itu highway, in Itu LGA of Akwa Ibom State, Nigeria with the aim of ascertaining whether the earth material at the study location is suitable for road construction. We carried out proctor’s compaction test, sieve analysis, California bearing ratio test and Attenberg’s limit test to analyse the clay samples for moisture content, California bearing ratio, plasticity and plastic limit, dry density and particle sizes. Results obtained indicate that the clay sample has an optimum moisture content of 13.53 %, dry density value in the range: 1580 kgm-3-1650 kgm-3, plastic limit of 22.15 %, plasticity index of 23 %, liquid limit of 45.63 %, sieve of 43.36 % with particles less than 0.075 mm and no particle size up to 5.0 mm, California bearing ratios of 9.0 % at 10.0 % moisture content, 6.7 % at 12.0 % moisture content, 2.0 % at 14.0 % moisture content. Based on these results, the clay sample is regarded as a sub-grade material with the classification of A-7-6 according to AASHTO (American Association of State Highway and Transportation Officials) classification. These results make the sample unsuitable for road construction but qualify it as a potential raw material for production of ceramic wares and tiles.