Development of properties as a function of temperature

A comprehensive test series has been undertaken in the Expert Centre in order to investigate the applicability of Freisleben-Hansens maturity concept from 1977 [1] to modern concretes exposed to aggressive environments. This involves an examination of the influence of the curing temperature on the development of properties such as compressive strength and resistance against chloride ingress.

Preliminary results indicate that the original maturity function probably needs to be revised in order to be consistent with the types of concretes used nowadays. The investigations have also revealed some very interesting and surprising behaviour regarding to the chloride migration coefficient (CMC): For pure CEM I concretes, the CMC at similar maturity increases with increasing curing temperature, whereas the opposite is observed for the fly ash concretes, i.e. the resistance to chloride ingress is greatly improved for fly ash concrete by high-temperature initial curing. These findings have been confirmed by a series of experiments with heat curing of concrete in isolated form work.

An extended abstract and two presentations dealing with the abovementioned results can be seen here:

Extended abstract from NCR workshop on Durability Aspects of fly Ash and Slag in Concrete (2012): Influence of curing temperature on development of compressive strength and resistance to chloride ingress of concrete with different binder systems

Development of properties as a function of temperature_NCR workshop Oslo

Development of properties as a function of temperature_Example of practical application


Recently, a further investigation have been undertaken at the Expert Centre with aim of (1) testing the applicability of the maturity concept to modern concretes and (2) to investigate the effect of the curing history of laboratory samples cured at elevated temperatures.

This investigation actually shows that the commonly used maturity concept is still applicable to modern concretes. Concerning the impact of curing history, interesting findings include that at 28 days of maturity, the strengths of concretes cured at a constant temperature of 60 °C are significantly lower than the strengths of similar concretes cured at 20 °C. For concretes exposed to a gradually increasing temperature going from the curing temperature to 60 °C, only a slight decrease in strength is observed for the pure cement concretes while the strength of the concretes with binder systems containing fly ash actually increase. Results from the investigation can be found here:

Test of maturity concept and influence of curing temperature on strength development of concretes (in Danish)

[1] FREISLEBEN-HANSEN P AND PEDERSEN J, Maturity Computer for Controlled Curing and Hardening of Concrete. Nordisk Betong, Vol. 1, 19-34, 1977.