Properties of early-stage concrete with setting-accelerating tablet in cold weather

Various methods are used at the early stages to control setting-time and strength of concrete, when cold-weather concrete is utilized. Among these methods is one that involves the use of an accelerator. Although economical, accelerators have difficulty securing workability because their early hydration makes them react rapidly. Therefore, how to make a tablet for cold-weather concrete, as with the existing medicines and foods, is discussed in this study, including the following items: mortar setting-time, workability by elapsed time, early strength to assure the development of adequate strength, and freezing–thawing resistance. As a result, both the 0.5 and 1.0% tablets were found to be superior. Thus, workability can be secured, as well as the development of early strength to prevent early frost.

► Tablets were used as accelerators, which have a merit in cold weather.
► Tablets are almost not used at all as construction materials (powdered admixtures).
► 0.5 and 1.0% tablets satisfied workability and strength for early-frost prevention.
► It was found that it is possible for the 0.5 and 1.0% tablets in cold weather.