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#HIGH STRENGTH CONCRETE MIX DESIGN CALCULATOR HOW TO#

The use of air entrainment in high strength concrete will greatly reduce the strength potential.

The total cementitious material content will be typically around 700 lbs/yd3 (415 kg/m3) but not more than about 1100 lbs/yd3 (650 kg/m3).

A Type A water reducer may be used in combination. These low w/cm ratios are only attainable with quite large doses of high range water reducing admixtures (or superplasticizers) conforming to Type F or G by ASTM C 494. W/cm ratios can be in the range of 0.23 to 0.35.

High strength concrete mixtures generally need to have a low water-cementitious materials ratio (w/ cm).Most mixtures contain one or more supplementary cementitious materials such as fly ash (Class C or F), ground granulated blast furnace slag, silica fume, metakaolin or natural pozzolanic materials. High strength concrete mixtures will have a high cementitious materials content that increases the heat of hydration and possibly higher shrinkage leading to the potential for cracking.The sand may have to be coarser than that permitted by ASTM C 33 (fineness modulus greater that 3.2) because of the high fines content from the cementitious materials. Generally smaller maximum size coarse aggregate is used for higher strength concretes. They need not necessarily be hard and of high strength but need to be compatible, in terms of stiffness and strength, with the cement paste. Aggregates should be strong and durable.Some of the basic concepts that need to be understood for high strength concrete are:

Optimum concrete mixture design results from selecting locally available materials that make the fresh concrete placeable and finishable and that ensure the strength development and other desired properties of hardened concrete as specified by the designer.

#HIGH STRENGTH CONCRETE MIX DESIGN CALCULATOR HOW TO#

HOW to Design High-Strength Concrete Mixture? (Note that high strength concrete does not guarantee durable concrete.) Some of these applications include dams, grandstand roofs, marine foundations, parking garages, and heavy duty industrial floors.

To satisfy the specific needs of special applications such as durability, modulus of elasticity, and flexural strength.

To build the superstructures of long-span bridges and to enhance the durability of bridge decks.

To build high-rise buildings by reducing column sizes and increasing available space.

To put the concrete into service at much earlier age, for example opening the pavement at 3-days.

The production of high strength concrete requires more research and more attention to quality control than conventional concrete. The compressive strength is measured on 6 × 12 inch (150 × 300 mm) or 4 × 8 inch (100 × 200 mm) test cylinders generally at 56 or 90-days or some other specified age depending upon the application. It is a type of high performance concrete generally with a specified compressive strength of 6,000 psi (40 MPa) or greater. Information from the National Ready Mixed Concrete Association WHAT is High Strength Concrete?