ABSTRACT
This chapter reviews the history and technical basis of the maturity method, a technique for estimating the strength gain of concrete based on the measured temperature history during curing. The combined effects of time and temperature on strength gain are quantified by means of a maturity function. Various maturity functions are reviewed critically. It is shown that the traditional Nurse−Saul maturity function is inferior compared with the function based on the Arrhenius equation. The concept of equivalent age, which is the most convenient measure of maturity, is explained. The strength gain of a specific concrete mixture is estimated using the measured maturity and the strength vs. maturity relationship for that mixture. Various proposed strength−maturity relationships are reviewed. It is explained why the maturity method can only be used reliably to estimate relative strength. Examples are presented to illustrate how this technique can be used in combination with other in-place tests of concrete strength. The ASTM standard dealing with the method is also summarized.
