Abstract

Control of cracks caused by the heat of hydration is one of the most important research themes in the design and construction of mass concrete structures such as dams from the view point of functions and durability of structures.
Low heat type cement, embedded pipe cooling and precooling are commonly used for controlling thermal cracks of concrete dams.
This paper discusses about the methodology and applications of precooling usin -196°C liquid nitrogen through the investigations upon the actual uses in Japan and other countries. The effect of precooling is also presented.