ABSTRACT
This study was aimed at investigating the causes of premature failures on Zaria - funtua Road linking Zaria in Kaduna state and Funtua in Katsina State. The road was asphalted in 1979. The riding quality on the road had deteriorated in the past couple of years with sections of the road developing various types of distress. Both field and laboratory tests were carried out. Results were utilized to draw conclusions on the type of axle loading, quality of construction materials and efficiency of the construction. On the whole, it was found that the failures were mainly caused by heavy axle load, use of poor strength materials and low degree of compaction. The degree of compaction was generally less than the desired 100%, whereas 42% of axles sampled exceeded the ten tons legal limit specified. The values of Atterberg limits did not meet the Federal specifications of minimum of 30% for the liquid limit and 12% for plasticity index. Also, the C.B.R. values were found to be below the minimum of 00% for base, 30% for sub-base and 5% for the subgrade set-out by the Federal specifications. Finally, both short and long term measures have been recommended to remedy the situation.