Modulus Of Elasticity Of Concrete

The modulus of elasticity of concrete E c adopted in modified form by the ACI Code can be calculated by the formula given below:

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Job Mix Concrete Volume

A trial batch of concrete can be tested to determine how much concrete is to be delivered by the job mix. To determine the volume obtained for the job, add the absolute volume V a of the four components—cements, gravel, sand, and water.

Find the V a for each component from

V a = W L / ( SG ) W u

where V a = absolute volume, ft 3 (m 3 )

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Water/ Cemetitous Materials Ratio

The water / cementitious (w/c) ratio is used in both tensile and compressive strength analyses of Portland concrete cement. This ratio is found from

w / c = w m / w c

where w m = weight of mixing water in batch, lb (kg); and w c = weight of cementitious materials in batch, lb (kg).

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Electrically Conductive Concrete: Properties and Potential

By Kelly Baldwin

Published in Construction Canada, v. 98, no. 1, Jan./Feb., 1998, pp. 28-29

Abstract: Conductive concrete is a cement-based composite that contains electronically conductive components to attain stable and relatively high conductivity. Potential applications include electrical heating for de-icing of parking garages, sidewalks, driveways, highway bridges, and airport runways, as well as electrical grounding.

Résumé: Le béton conducteur est un composite à base de ciment contenant une certaine quantité d’éléments qui assurent une conductivité électrique stable et relativement élevée. Les applications possibles sont : le chauffage électrique pour dégivrer les garages de stationnement, les trottoirs, les voies d’accès, les ponts routiers et les pistes d’aéroport, et la mise à la terre électrique.
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