Effect of Steam Curing on Initial Strength Development of Mortar

Abstract

The steam curing process is being applied to produce precast concrete to accelerate production cycle. A prediction of initial strength is required to determine optimized production cycle and provide economical mix proportions. As for this, the strength estimate by the Maturity method is being used widely so far. However, this method is pointed that the accuracy of the estimated strength of the concrete which has been steam cured is low. This is one of the problems on the precast concrete production. In this study, the relationship between initial strength at early age and effective material age calculated by Maturity method and Arrhenius's law was evaluated. As a result, it showed a higher estimation accuracy of the Arrhenius's law than the Maturity method. However, the accuracy of the prediction was different in each condition such as cement type, water-cement ratio, and steam curing temperature and material age.

Experimental study of accelerating early age concrete strength under elevated temperature, steaming, and chemical admixture addition of normal and high strength concrete

“…A relationship between initial strength at early age of concrete calculated by Maturity Method and Arrhernius Law was evaluated using experiment investigation. The experiment use cube specimens of size Ø50x100 with various water-cement ratios of 30%, 40%, 50% and exposed under curing temperatures variations of 10 o C, 20 o C, 30 o C. The accuracy of the prediction was different in each condition such as cement type, water-cement ratio, steam curing temperature, and material age [10]. By promoting cement hydration, raising steam curing temperature to 70 o C could significantly increase initial compressive strength as well as the permeability of concrete specimens.…”

Accounting for the Influence of Heat-Moisture Treatment Mode When Designing Concrete Composition

“…Calculating the required cement-water ratio for steamed concrete becomes much more complicated, especially in achieving the required concrete strength immediately after steaming. As shown by practical experience and many studies [3][4][5][6][7][8][9][10][11][12][13], the strength of concrete after steaming is significantly affected by its mode parameters. It affects both the value of the cement strength realized in concrete and the required C/W to achieve a given strength.…”