Reactive powder Concrete
1. Introduction
Reactive Powder Concrete (RPC) was developed by P. Richard and M. Cheyrezy and was first produced at Bouygues’ laboratory in France2 early 1990s. In July 1997, the Sherbrooke Bridge in Quebec, Canada3, became the world’s first structure to be constructed entirely out of Reactive Powder Concrete. Due to its extreme low permeability it is also being used for containment of nuclear waste in Europe4.
Reactive Powder Concrete (RPC) is basically a special concrete where the microstructure is optimized by precise gradation of all the constituent particles to produce a maximum possible density. This results in achievement of a composite with extremely high strength (compressive strengths ranging from 200 MPa to 800 MPa) and also high ductility (due to addition of steel fibers) along with improved mechanical and physical properties (low permeability etc.). RPC also extensively uses the pozzolanic properties of highly refined silica pozzolans and optimization of the Portland cement chemistry to produce the highest strength hydrates1 without use of course aggregates. Thus RPC is a Ultra High Strength Concrete (UHSC).
2. Composition of Reactive Powder Concrete
RPC is essentially composed of very fine powders:
• Cement
• Sand
• Quartz powder
• Silica Pozzolan (Microsilica, Silicafume etc.)
• Steel fibers (optional)
• Super plasticizer
The aim is to achieve a very dense matrix using extremely low water/binder (w/b) ratio (0.13-0.24) and by optimizing the granular packing of the dry fine powders. The resulting compactness gives RPC ultra-high strength and durability6. Table 1 shows the various components of RPC and their selection parameters.
3. Reactions taking place
• Cement hydration
2C3S + 6H ...
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...ngs like roofs for stadiums, long bridge spans, and anything that needs extra safety or security such as blast resistant structures
• Its low permeability and high strength makes it ideal for storing nuclear waste.
8. Disadvantages
• The constituents are expensive which limits its usage
• There is no proper code standardizing the mix
9. References
1. Richard P, and Cheyrezy M, “Composition of Reactive Powder Concrete”, Cement and Concrete Research, Vol. 25, No.7, (1995), pp. 1501 – 1511.
2. Aitcin P.C, “Cements of yesterday and today Concrete of tomorrow”, Cement and Concrete Research, Vol. 30, (2000), pp 1349 - 1359.
3. Khadiranaikar R.B. and Muranal S.M. (2012) “Factors affecting the strength of Reactive powder Concrete(RPC)” International Journal f Civil Engineering and technology volume 3 issue 2
4. Chrisholm D.H. and Lee N.P. (2005) “Reactive Powder Concrete”
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