RAPID STRENGTH CONCRETE
Rapid Strength Concrete is a type of concrete that has the ability to gain high strength in a short period of time. From time to time, the application of this type of concrete has been implicated in roads and bridge improvement projects, and the most common application of RSC is to repair roads. This type of concrete is similar to regular concrete, with steel bar as reinforcement. The difference is the process of making this concrete mixture requires more testing to carefully plan the quality desired. The quality of this concrete is its durability, ability to gain high compressive strength within hours, and ability to withstand corrosion.
Ridho Bayuaji, a researcher from Sepuluh Nopember Institute of Technology has made a review in this high early strength concrete. From his research, in the primary 24 hours after site-pouring, the compressive strength of RSC can reach the structural quality of the concrete with compressive strength of more than 21 MPa. In the manufacturing process, 4 factors affect the high initial strength mechanism that is: cement content, Portland cement type, the ratio of water to cement, and the admixture. The admixture that is used in the mixing process is the type that reduces water and accelerates the hydration process. It is estimated that the production cost of RSC is 25 to 30% more expensive compared to standard concrete.
There are two ways of mixing RSC, mechanically or manually. One important aspect that needs to be taken into concern is the water content in the mixture, as too much water may result in slower strength gain, lower compressive strength, and increase the possibility of shrinkage cracking. Followed by the U.S. and China, Europe leads the most consumption of rapid strength concrete in the global market.
Yasin, A.K., Bayuaji, R. and Susanto, T.E., 2017. A review in high early strength concrete and local materials potential. MS&E, 267(1), p.012004.
Moffatt, E.G. and Thomas, M.D., 2018. Durability of rapid-strength concrete produced with ettringite-based binders. ACI Materials Journal, 115(1), pp.105-115.