The maturity method for measuring concrete strength produces an estimate of strength based on the actual temperature history experienced by the concrete in place. As such, the maturity method attempts to address the differing hydration rates experienced by test specimens compared to the concrete in place. The maturity method requires development of a strength-maturity relationship that is specific to the mixture. Application of maturity has been increasing and certain state agencies have made it a standard test for determining when to open concrete highway pavement to public traffic. Use of maturity in the airport environment has been limited. Potential benefits to the airfield concrete pavement industry includes:

Decreasing time to open critical areas to traffic (such as intersections, runway ends and full panel replacement), Shortening the time between staged paving operations, Improving joint sawing operations, Reducing the number of strength tests, and Improving reliability of acceptance techniques through testing in-place material. Conventional use of maturity testing requires a maturity index value (also called a time-temperature factor, or TTF) or an "equivalent age" value to be read from a maturity meter and/or calculated from a time-temperature profile. This maturity index value (or equivalent age) must then be compared to the established strength-maturity relationship curve to convert it to a strength value. Technology is on the edge of being able to automate this conversion and provide information in units that a contractor or engineer can understand in real time.

The primary limitation of conventional maturity measurement stems from the need to convert the temperature readings from embedded thermocouples, or the degree-hours (i.e. TTF) units from maturity devices, to strength values.

Instructions for the submittal of proposals for this demonstration project can be found at www.iprf.org and follow links for Project 4.