Hot-poured crack sealants are widely accepted as a cost-effective, routine preventive maintenance practice that extends pavement service life three to five years when properly installed. However, current ASTM specifications for selection of crack sealants correlate poorly with field performance. Therefore, an improved sealant specification and selection system is urgently needed. Recently, performancebased guidelines were developed by the pool-fund North American Consortium expert group for selecting hot-poured bituminous crack sealants. The work proposed a sealant grade (SG) system for selecting hot-poured crack sealant based on environmental conditions. A special effort was made to use the equipment originally developed by the SHRP, which was used to measure binder rheological behavior as part of the performance grade (PG) system. The equipment and testing procedures used for performance grading of binders were modified in accordance with crack sealant behavior. The main objective of this study was to validate the low-temperature selection thresholds for the newly developed performance-based guidelines for selecting hot-poured crack sealants. Thresholds for the crack sealant bending beam rheometer (CSBBR), crack sealant direct tension test (CSDTT), and crack sealant adhesion test (CSADT) were validated. Nine hot-poured crack sealants were installed in four test sites experiencing low-temperatures. The field performance of crack sealants was evaluated for two consecutive years by conducting detailed field surveys. The field database consisted of 40 sections containing 647 cracks. Overall, results showed good correlation between the proposed selection thresholds and sealant performance in the field.
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