Although diamond grinding of jointed concrete pavements has beenused in the united states since 1965 to remove faults and improve rideability, no documentation of its performance nationwide has been available until now. As part of a study of eight concrete pavement rehabilitation techniques conducted by the university of illinois forfhwa, 76 diamond grinding projects in 19 states were surveyed and analyzed. Diamond grinding is an effective means of improving ride quality on pavements with faulted joints, cracks, and repairs. The rideability of a newly ground pavement is typically as good as or better than that of a newly constructed pavement. However, if no other restoration work except grinding is performed on pavements with poor subdrainage, slab support, and load transfer, faulting after grindingrecurs at a faster rate than for newly constructed pavements. Otherfactors found to significantly affect the performance of diamond grinding include traffic, slab thickness, joint spacing, base type, subgrade type, and climate. Surprisingly, dowel bar diameter was not found to be significant to the prediction of faulting after grinding.By the time faulting reaches objectionable levels, dowels may already be so loose that they contribute little to load transfer. More than 20% of the grinding projects surveyed had large amounts of cracking (more than 825 ft/lane-mi), and probably should have been overlaid or reconstructed rather than restored. The full benefit of diamondgrinding, in terms of pavement life extension and cost effectiveness of repair, is not likely to be achieved on such pavements, which are likely to require major structural rehabilitation long before appreciable faulting recurs. This paper appears in transportation research record no. 1268, Highway maintenance operations and research 1990.
Abstract