ASSESSMENT OF ROAD FAILURE (A CASE STUDY OF DAKINGARI SABON BIRNI AREA)

ABSTRACT Road infrastructure plays a vital role in socio-economic development by facilitating mobility, trade, and accessibility. However, many roads in Nigeria experience early failures despite huge investment in their construction. This study assessed the causes of pavement failure along the Dakingari–Sabon Birni Road in Kebbi State. Both field observations and laboratory tests were carried out to evaluate the condition of the road and the engineering properties of the soil and materials used. Field surveys revealed widespread pavement distress, including potholes, cracks, rutting, and surface depressions. A total of 52 potholes covering approximately 136.8 m² were recorded along different chainages, with most occurring in poorly drained sections. Laboratory tests, including Atterberg limits, sieve analysis, compaction, and California Bearing Ratio (CBR) tests, were conducted on soil samples. Results showed that the soils had liquid limits between 31–33%, plastic limits of 22–27%, and plasticity indices of 4–9%, all within acceptable limits for subgrade materials. Compaction tests indicated maximum dry densities of 1.94–2.29 g/cm³ at optimum moisture contents between 10–15%, while CBR values ranged from 25% to 75%, meeting Nigerian road design standards.The findings demonstrate that the road failures are not primarily due to poor material properties but rather to inadequate drainage, poor construction practices, lack of timely maintenance, and vehicle overloading. It is therefore concluded that improving drainage systems, enforcing strict quality control, regulating axle loads, and adopting routine maintenance measures are critical to prolonging the service life of the road.