Investigation on the Engineering Properties of Road Pavement Failures “(A Case Study of Portion of Malam Aminu Kano Way, Kano State from Tal-Udu Roundabout to Mambaya House Roundabout)”

Abstract

Investigation upon engineering properties into the causes of road Pavement Failures “(A Research Study of Segment of Malam Aminu Kano Way, Kano State from Tal-udu Junction to Mambaya house Roundabout) Dala government of Kano state, was carried out. Visual condition survey was carried to assess the types and degrees of distresses. The results showed that, the portion of road was in a bad condition as at the time of this study. Soil samples of various layers were collected and the geotechnical properties were tested for. The test results revealed that, for CBR value ranges from 23.77% to 26.35% with an average value of 24.92%, for sub-grade, and CBR values ranges from 82.3% to 92.8% with an average value of 87.55%. According to the specification of the Federal Ministry of Works and Housing of Nigeria, Clause 6201, for materials to be suitable for base course and sub-base, it must have liquid limits of not greater than 35%, plasticity not greater 12% and CBR value of not less than 30% (24 hours soaking). For sub-grade, liquid limits must be higher than 50% plasticity index of not more than 30% and CBR value of minimum of 6% (24 hours soaking). Therefore, the results showed that, the road-base materials were not fit in terms of Liquid Limit (LL) and Plasticity Index (PI) specifications. But sub-base and sub-grade, satisfied both Liquid Limit and Plasticity Index specifications. The road-base and the sub-base were found not satisfying the California Bearing Ratio (CBR) specifications, but the sub-grade did. The drainage and materials used for the construction especially, the base and sub-base were one of the major causes of pavement failures of the road portion. However, recommendations were provided, among which includes: suitable materials should be used for pavement construction; Drainage should be properly constructed and maintained after construction; more research should be carried out on this same in order to establish other causes of its failures.