non sono un esperto però ho trovato il link sotto che fa al tuo caso.
Se non ho capito male, l'espressione "maturity method" indicherebbe il grado di "maturazione" ovvero di "utilizzo" del cemento. In sostanza, il tempo e la temperatura idonei per garantire il grado di resistenza ottimale del materiale."The maturity method is a technique to account for the combined effects of time and temperature on the strength development of concrete. The method provides a relatively simple approach for making reliable estimates of in-place strength during construction. The origin of the method can be traced to work on steam curing of concrete carried out in England in the late 1940s and early 1950s. As a result of technology transfer efforts by the Federal Highway Administration, there is renewed interest in the method within the United States. The purpose of this paper is to review of the basic concepts underlying the method and to explain how the method is applied. The review focuses on work carried out by researchers at the National Institute of Standards and Technology (formerly the National Bureau of Standards)". Se non esiste un termine tecnico specifico, lo tradurrei come "metodo per la determinazione del grado di maturazione del cemento." Sarà un pò lunghetto, ma rende l'idea.