ANALYSIS OF ROAD PAVEMENT FAILURE DUE TO SOME SOIL PHYSICAL PROPERTIES ALONG WARRI-SAPELE HIGHWAY, DELTA STATE, NIGERIA

ABSTRACT

This study examined the causes of persistent road pavement failure at Okuovwori, Okolovu and Akuekpara along the Warri-Benin highway, Delta state, Nigeria. Morphological, Physio-Chemical and Physical analyses were conducted to evaluate the cause of failure along the study area. Soil samples were collected from the failed sections and subjected to laboratory tests, revealing critical insights. Based on the general specification for roads set by the Federal Ministry of Works and Housing (1997), the particle size distribution of Okuovwori and Okolovu samples were not acceptable while Akuekpara sample was appropriate. The liquid limit in all locations where above 50% which is signifies high plasticity and unfavourable moisture retention. The optimum moisture content for all 3 locations ranged between 7.30% -13.0% indicating potential drainage challenges. The Maximum Dry Densities (MDD) for all locations ranged between 1.52 to 2.18%.  California Bearing Ratio (CBR) values for the Base course in all the samples met specification requirements. From the analysis, it's apparent that the prevailing soil properties fall below optimal conditions for road construction, within the context of Nigerian standards. A practical solution lies in soil improvement methods, with soil stabilization emerging as a viable approach. By bolstering soil strength and stability, these methods offer potential to extend the road's lifespan and mitigate recurrent pavement failures.