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Publication Citation: Computer Modeling of the Replacement of Coarse Cement Particles by Inert Fillers in Low W/C Ratio Concretes: Hydration and Strength

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Author(s): Dale P. Bentz; J T. Conway;
Title: Computer Modeling of the Replacement of Coarse Cement Particles by Inert Fillers in Low W/C Ratio Concretes: Hydration and Strength
Published: March 01, 2001
Abstract: In concretes with water-to-cement (w/c) ratios below about 0.38, a portion of the cement particles will always remain unhydrated due to space limitations within the material. Thus, in many of the high-performance concretes currently being produced, cement clinker is in effect being wasted. This communication examines the possibility of replacing the coarser fraction of a cement powder by an inert filler, to conserve cement without sacrificing material performance. Using the NIST CEMHYD3D cement hydration model, it is demonstrated that for initial w/c ratios of 0.25 and 0.30, a portion of the coarser cement particles can be replaced by inert fillers with little projected loss in compressive strength development. Of course, the optimal replacement fraction depends on the initial w/c ratio, suggesting that blended portland/inert filler cements need to be produced with the end concrete mixture proportions in mind. This further implies that a cement/inert mixture of specific proportions will only perform optimally in a limited range of concrete mixture proportions.
Citation: Cement and Concrete Research
Volume: 31
Issue: No. 3
Pages: pp. 503 - 506
Keywords: blended cements;compressive strength;hydration;modeling;particle size distribution
Research Areas: Building and Fire Research
PDF version: PDF Document Click here to retrieve PDF version of paper (290KB)