Volume 1, Issue 7 (July 2004)
Developing a Performance-Based Joint Sealant Specification for Airport PCC Pavements
Despite recent progress to develop a performance-based specification for bituminous sealants applied to asphalt concrete (AC) roadways and runways, a performance-based specification for cold-applied joint sealants for Portland cement concrete (PCC) aprons, taxiways, and parking areas has yet to be mapped and developed. Unique in-service conditions exist on these PCC pavements, where sealants are not only exposed to climatic effects and heavy traffic loads, but also to jet fuel and de-icing fluids. Installation and maintenance conditions are also unique in that it is often necessary to install or replace joint sealants at night or in a very short time so that aircraft traffic disruption is avoided. Hence, special consideration must be provided to ascertain that joint sealants are effective and durable. Recent studies on joint and crack sealants used on airport pavements that experience cold climates indicate that current specifications do not necessarily allow for the selection of durable sealants, and therefore sealant failure can be rapid. To address the issue of premature failure and to extend joint sealant service life, the elements of a performance-based specification for cold-applied joint sealants for PCC airport pavements is reviewed. The benefits of such a specification include the selection of joint sealants for specific local needs, reduced airport pavement maintenance costs, and extended airport PCC pavement service life.