A strength model for no-slump concrete with fly ash

The current paper presents a model for predicting compressive strength of no-slump concrete with and without fly ash by considering the effect of elevated curing temperature. The model was constructed based on the current authors' test results of compressive strength of no-slump concrete. Additionally, the influences of other parameters, such as mix proportion, chemical composition and physical properties of binders, were also taken into account. The model was established based on a relationship between gel/space ratio of paste and compressive strength development ratio of concrete. In the present study, the gel/space ratio concept for cement paste proposed by Powers and Brownyard in 1946 was adopted and extended for cement–fly-ash system application. The gel/space ratio was found to have a good correlation with compressive strength development ratio of concrete. The proposed model was calibrated and verified by the data obtained from the studies of the current authors and other researchers. The verification of the model showed satisfactory accuracy.