Temperature Control of Precast Concrete Subjected to Steam Curing
By H. Sakuraba, H. Koga and K. Inoue
Concrete Journal, Vol.60, No.11, Nov. 2022
- Synopsis
- Precast concrete is manufactured using steam curing to accelerate strength development and allow early demolding. However, deterioration caused by delayed ettringite formation (DEF) in the case of excessively high concrete temperatures is a concern. In this study, we investigated the actual conditions of steam curing facilities and conducted experiments under conditions reproducing actual production, and we investigated temperature control methods for the suppression of DEF. Based on the results of the experiment, points to be kept in mind regarding the measurement position of the ambient temperature and the specification and position of the steam outlets for controlling steam were determined. Further, it was determined that when a member is thick and thus ought to be considered as mass concrete, the concrete temperature may exceed 70℃, which is the concrete temperature level at which DEF may occur, depending on the production conditions.
- Keywords:
- Precast concrete, Steam curing, Temperature control, DEF
