Long-Term Performance of Broken and Seated Pavements

A study was developed to evaluate the effectiveness of breaking and seating (B/S) as a rehabilitation strategy for retarding reflective cracking in asphalt concrete (AC) overlays on jointed reinforced concrete pavements (JRCP). Several test sections were constructed by milling the original AC layer, breaking and seating the concrete slabs, and constructing new AC overlays. Control sections were constructed adjacent to the B/S sections in the same way, but without breaking the underlying concrete slabs. Two types of pavement breakers were used in this study: guillotine and pile hammer. The majority of the concrete slabs were broken into 0.46-m (18-in.) segments. Performance of the test sections was monitored for a total period of 9 years. Breaking the concrete slabs into smaller pieces resulted in a reduction in the flexural strength, an increase in the surface deflection (50% to 100%), and a decrease in area and spreadability (20% to 30%). Within 2 to 4 years, reflection cracks developed over more than 80% of the joints in all the control sections. The B/S sections were relatively free of cracks after 9 years. This result clearly indicates that breaking and seating has been extremely effective in minimizing and delaying reflection cracking. Based on the results of this study, it was concluded that breaking and seating is an effective technique for the rehabilitation of composite pavements (AC over JRCP). It provides an effective solution for the maintenance and rehabilitation of in-service composite pavements.