Evaluation of Pavement Surface Distress on Major Roads in Kaduna Metropolis, Kaduna State

Pavement surface distress on major urban roads in Kaduna metropolis, North West Nigeria, reduces road user safety, increases vehicle operating costs, and imposes economic burdens on the state's road maintenance budget. This study evaluates surface distress conditions on eight major roads in Kaduna metropolis using systematic pavement condition surveys. Visual surveys were conducted using the ASTM D6433 Pavement Condition Index manual procedure on 3 km sections of eight roads in Kaduna North and Kaduna South LGAs. Distress types, severities, and quantities were recorded on standard survey forms. Traffic count data and pavement age information were collected from the Kaduna State Ministry of Works. Pavement Condition Index scores were calculated and used to derive maintenance priority rankings. Results show that 62 percent of surveyed road length has a PCI below 40, classifying it as Poor or Very Poor. Rutting and corrugation are the dominant distress types in areas of high heavy vehicle traffic. Alligator cracking is prevalent on roads with base drainage deficiencies. Two roads have PCI values below 20, classifying them as Failed. Mean PCI across all surveyed sections is 32, indicating a network in urgent need of rehabilitation. The study recommends a three-tier maintenance programme: routine pothole patching for PCI above 40, overlay rehabilitation for PCI 20 to 40, and full reconstruction for PCI below 20.

Keywords: pavement condition index, surface distress, road maintenance, Kaduna metropolis, pavement management