Concrete compositions, production

The concrete composition and the constituent materials for designed or prescribed concrete are chosen to satisfy the requirements specified for fresh and hardened concrete, taking into account the production process and the intended method of execution of concrete works. A single mix has to be defined that is able to satisfy all the requirements. The procedure used for selection of a concrete mix (type and proportion of cement, water, aggregate, and admixtures) is called the mix design. Several procedures for mix design can be found in the technical literature, which are based on empirical correlations that associate the requirements for concrete to different parameters of its composition, such as the w/c ratio, the water content, etc. [4,10-12]. Some of these parameters are associated with more than one of the requirements. This is the case for the wjc ratio. 

The mechanical properties, the corrosion stability, and some useful properties are the reasons for the continuous interest shown in polymer-concrete composites by various design, research, and production organizations. The most important types of polymer-concrete composites are polymer-impregnated concrete (PIC), polymer-cement concrete (PCC), and polymer concrete (PC). 

Simatupang, M.H. et al. (1995) Investigations on the influence of the addition of carbon dioxide on the production and properties of rapidly set wood-cement composites. Cement and Concrete Composites 17,187-197. 

Pioro, L. and Pioro, 1., 2004. Production of Expanded-Clay Aggregate for Lightweight Concrete from Non-Selfbloating Clays, Int. J. Cement Concrete Composites, 26 (6), pp. 639-643. 

Applications concrete, composites, dielectric material, fibers, production of carbon fiber, clothing, awnings, beach umbrellas, boat covers, car tops ... 

There are ontlets for mixed plastics, but because of the heterogeneous composition of the raw materials they are limited to the production of large components. This is so that contaminants and any material that has not melted and mixed will not have a great effect on the overall strength. Often products of this type find outlets as plastic lumber or concrete replacement products such as park tables, slabs or benches, where the non-rotting properties of plastics can be utilised. 

Ethoxylated or propoxylated fatty alcohol acrylate or methacrylate compoimds are useful as defoamers for concrete compositions (28). It has been observed that a special balance between the chain length of the fatty alcohol and the distribution of the ethoxy or propoxy units results in an ester with improved defoaming properties. These products are particularly efficient in removing occluded air bubbles and foams formed during concrete processing operations. This is unusual, since the structures miss polymeric backbones. 

Conventional wisdom on the durability of polymer composites is that FRP composite products can be in-service for a very long time unlike steel or concrete. FRP composite materials can provide a longer service life because of lower therm effects, better mechanical performance, and higher damage tolerance than conventional materials provided they are tailor-made with a high degree of precision... 

Figure 1.17 illustrates the multiscale model from fiber to final product. This book has a focus on fibers, yarns, and textiles. Together with a matrix material, such as resin and concrete, composite structures can be manufactured. 

Richardson, I. G. 2000. The Nature of the Hydration Products in Hardened Cement Pastes . Cement and Concrete Composites 22 (2) 97-113. 

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