Effect of Heavy Vehicle Traffic on Benin – Auchi Road, Ekpoma Axis

The continuous deterioration of pavement in Ekpoma has been adduced largely to the rapid increase in heavy vehicles carrying much in excess of permitted legal limits. The present study investigated levels of deterioration caused by heavy vehicles through 14days’ traffic counts conducted at 5 strategic points each in the city. Traffic data generated from vehicle count were analyzed with AASTHO Designs Guidelines (1993) to evaluate Equivalent Single Axle Loads (ESALs) and vehicle damage effects on the road. The Traffic Volume, Average Daily Traffic (ADT) and Heavy Vehicle per day (HV/day) were 694,023, 49,573 and 19,239 respectively. Motorcycles, passenger cars, mini buses/pick – ups and heavy vehicles constitute about 6.3% (44,059), 37.9% (262,743), 19.9% (117,878) and 38.8% (269,343) of the total traffic volume respectively. An average Load Equivalency Factor (LEFs) was estimated for the heavy vehicles plying the road to be 3.06 and this could explain some failures (alligator cracks, potholes, depressions, linear or longitudinal cracks along the center line amongst others) inherent on the road. Installation and operation of weigh bridges in strategic locations are essential to monitoring and regulating the axle loads of heavy vehicles using Nigerian roads, ensuring that they do not exceed the maximum allowable load limit prescribed in pavement design specifications.