Evaluation of Concrete Pavement Rehabilitation Techniques on I-65 in Indiana

Construction of hot mix asphalt (HMA) overlays on top of old concrete pavements is the most common concrete pavement rehabilitation strategy. These overlays, however, usually are subject to reflection cracking related to the movement of the old concrete slab. In addition, these overlays may be vulnerable to rutting when subjected to large traffic volumes of heavy trucks. Concrete overlays have the advantage of being rut resistant compared with HMA overlays. However, the current national experience of the performance of these overlays is limited, compared with HMA overlays. Doubts often are raised about the cost-effectiveness of these overlays, the ease of their rehabilitation at the end of their design life, and the time required to close the road to traffic for ongoing and postconstruction operations. Presented is an evaluation of three concrete pavement rehabilitation techniques employed on I-65 in Indiana: (a) a fiber-modified HMA overlay on top of cracked and seated concrete pavement; (b) an HMA overlay on top of rubblized concrete pavement; and (c) an unbonded concrete overlay on top of 30-mm intermediate HMA layer on top of old concrete pavement. Evaluation of these techniques will continue until 2002. Performance of these rehabilitation techniques was assessed considering the performance of restoration (no overlay) techniques applied in 1985 on the same highway segment. It was concluded that all rehabilitation techniques performed satisfactorily. The unbonded concrete overlay segment exhibited the best performance in reflection cracks elimination, structural capacity, and skid resistance. The rubblized segment exhibited the best performance in ride quality and uniformity of structural capacity. Life-cycle cost analysis suggested that the unbonded concrete overlay was the most cost-effective segment.