Surface Condition Survey of the Thika Magumu Road (B20/D1315)

Abstract

In developing countries, large sums of money are spent annually to enhance and maintain road networks as allocated by road authorities. The road users’ needs in most countries all over the world is to have safe, economical, and smooth roads despite pressure on road authorities to further reduce expenditure. Money allocation for road infrastructure is among the many priorities competing for government funds thus causing the pressure. Proper rehabilitation strategies are therefore important to ensure the longevity and reliability of our road networks. The objective of this thesis was to evaluate the performance of Thika- Magumu road, identify the defects on the pavement, and finally find the best remedy for the defects established. This was done by visual inspection in which the road was inspected, and photographs taken. Surface regularity tests were carried out to determine the extent of ruts on the road. Roughness measurement was carried out to determine the roughness of the road, Present Serviceability Rating to verify the rating of the road, traffic analysis was done to determine the axle loading on the Thika- Magumu road and the effect on the pavement and the deflection of the road was measured using the falling weight deflectometer. There were different types of pavement distress that enhanced the cost of maintenance of this road. They included potholes, rutting, shoulder failure and cracks. These were corrected by pothole patching, overlay, reconstruction and crack sealing respectively. The usefulness of the research findings was that it gave a guide on the process to prolong the life span of the pavement as mentioned above, it gave an estimate of the remaining life of the pavement. The finding was archived for future use in Thika Magumu road and as a guide to any similar road. They were also crucial in prioritizing the roads that need maintenance and budgeting for the road authorities. The recommendations were; the need to reconstruct the road in sections were there was complete pavement failure and an overlay in sections were the defects were on the surface