THE COST EFFECTIVENESS OF RECYCLING OF ASPHALT PAVEMENT

The purpose of this study was to compare the cost effectiveness of recycled asphalt pavement with the roads constructed by conventional method in the State of Kansas. Data was collected from nineteen area engineers, eleven city engineers, seven county engineers, and twelve contractors in the asphalt recycling business. An analysis was made to compare the experiences of engineers and contractors. There was a general lack of experience of asphalt recycling among the county and city engineers. There was no apparent differences of experiences of asphalt recycling between the area engineers and contractors. An apparent difference was found between engineers and contractors on the number of projects they worked with during the last two years using different methods. Apparently there was no difference between engineers and contractors on the most often used method of asphalt recycling. Recycling of asphalt pavement has been widely accepted as an alternative means of restoring deteriorated roads. Among the different techniques of asphalt recycling, hot off-site plant recycling appeared to be cost effective as compared to conventional hot-mix. Hot off-site was most often used by contractors and engineers on projects. Cold in-place recycling was the most energy efficient method and produced less air pollution. Weather and heavy traffic conditions, however, made it deteriorate faster. Recycled asphalt pavement bases, whether hot in-place, hot off-site, cold in-place, or cold planing could be superior to conventional aggregate bases. The researcher believed that additional engineering effort would be required in connection with mix design and construction control. The selection of materials, techniques and equipment should be evaluated for the project before commencement. The availability of contractors with experience and equipment for recycling business should be identified within the locality of the proposed projects. The conditions of the pavement to be recycled should be evaluated before any recycling technique could be applied to that pavement. The researcher also believed there should be more intensive laboratory research on the performance and possible application of asphalt recycling methods or mixtures. More technical literature is needed on asphalt pavement recycling