Application of curing compound and steam curing in subyia project of Kuwait;

Hydration characteristics of steam curing cement-fly ash composite binder;

Using tests of compressive strength, hydration product and porosity, the influen ce of steam curing on the pozzolanic reaction of rejected fly ash were studied.

The result shows that the activity index of desulphurization ash is higher than fly ash in standard curing condition and in steam curing condition,but lower in Autoclave curing condition.

Combined with experiences steam-curing of precast box beam in winter four important temperature control stages in curing period are introduced in detail.

The strength decreasing and worse durability are the problems of the steam-curing concrete.

Aiming at the durability problems of steam-curing concrete used in the railway sleeper and bridge prefabricate structures, the paper studied the hydrate properties, pore strucrure, pore liquid alkalinity and carbonation depth of fly-ash concrete.

In this paper,through researching and analyzing the temperature control for the stream maintenance of concrete box girder in four stages,the temperature control parameters for stream maintenance of concrete box girder in winter are offered to guide precasting concrete box girder on site and ensure the precasting quality of the girder.