A ROAD DETERIORATION STUDY IN KENYA

The deterioration characteristics of roads and the ways in which these characteristics depend on the original design and construction standard, the natural environment, and the traffic loading were studied. Relationships were derived between the above variables and were esxpressed in a form suitable for use in a computer model. The effects of different maintenance policies on the deterioration of roads was also investigated. Details are given of the design of the experiments, the materials investigation, the traffic measurements, and road performance measurements. Experimental results (for paved and unpaved roads) are analyzed and the conclusions are presented. The model described here allows the calculation of the total costs (construction, maintenance, and vehicle operation) of a road project over a chosen design life and the study of the way these costs depend on road geometry, maintenance policy and construction standard. The lowest cost design will depend on many factors, the chief of which are traffic loading, traffic composition, design life, ground profile, location of road building materials, type of terrain and climatic conditions.