Geotechnical Investigation of Road Failure along Ilorin-Ajase –Ipo Road Kwara State, Nigeria.

Abstract

The incessant failure of road network in Nigeria has generated a lot of concern by road users and government. Apart from lives and properties that are lost annually to road crashes, road rehabilitation across the country has become a financial burden to the federal government. Several factors have been identified to be responsible to road failure in Nigeria; they include geological, geomorphological, road usage, bad construction and wrong approach to maintenance. Hence, this paper examines some of the factors responsible for road failure along Ilorin-Ajase Ipo road, Kwara State Nigeria. Soil samples were collected from Five (5) portions of the road that are badly affected by road failure. These portions include: Agricultural and Rural Management Training Institute (ARMTI) 17+800km, Kabba Owode 18+00Km, Idofian 23+700Km, Koko 29+700Km and Omupo 35+700Km axis. The soil samples collected were analyzed  four engineering properties: particle size distribution (PSD),atterberg limit, compaction test California Bearing Ratio (CBR). The result of Principal components indicated that, in the study area sandy soil contribute 50%,Coefficient of curvature account for  28.1% and coefficient of Uniformity 14.1%.T he overall results showed that poor foundation materials and poor Engineering construction have affected the rate of failure of the road along Ilori –Ajase Ipo road.