enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Properties of concrete - Wikipedia

    en.wikipedia.org/wiki/Properties_of_concrete

    Concrete has a very low coefficient of thermal expansion, and as it matures concrete shrinks. All concrete structures will crack to some extent, due to shrinkage and tension. Concrete which is subjected to long-duration forces is prone to creep. The density of concrete varies, but is around 2,400 kilograms per cubic metre (150 lb/cu ft). [1]

  3. Water–cement ratio - Wikipedia

    en.wikipedia.org/wiki/Water–cement_ratio

    A w/c ratio higher than 0.60 is not acceptable as fresh concrete becomes "soup" [2] and leads to a higher porosity and to very poor quality hardened concrete as publicly stated by Prof. Gustave Magnel (1889-1955, Ghent University, Belgium) during an official address to American building contractors at the occasion of one of his visits in the ...

  4. Reinforced concrete - Wikipedia

    en.wikipedia.org/wiki/Reinforced_concrete

    Concrete wall cracking as steel reinforcing corrodes and swells. Rust has a lower density than metal, so it expands as it forms, cracking the decorative cladding off the wall as well as damaging the structural concrete. The breakage of material from a surface is called spalling.

  5. Concrete - Wikipedia

    en.wikipedia.org/wiki/Concrete

    Concrete is a composite material composed of aggregate bonded together with a fluid cement that cures to a solid over time. Concrete is the second-most-used substance in the world after water, [1] and is the most widely used building material. [2] Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminium combined. [3]

  6. Density - Wikipedia

    en.wikipedia.org/wiki/Density

    Water density calculator Archived July 13, 2011, at the Wayback Machine Water density for a given salinity and temperature. Liquid density calculator Select a liquid from the list and calculate density as a function of temperature. Gas density calculator Calculate density of a gas for as a function of temperature and pressure.

  7. Specific weight - Wikipedia

    en.wikipedia.org/wiki/Specific_weight

    The specific weight, also known as the unit weight (symbol γ, the Greek letter gamma), is a volume-specific quantity defined as the weight W divided by the volume V of a material: = / Equivalently, it may also be formulated as the product of density, ρ, and gravity acceleration, g: = Its unit of measurement in the International System of Units (SI) is newton per cubic metre (N/m 3), with ...

  8. Compressive strength - Wikipedia

    en.wikipedia.org/wiki/Compressive_strength

    As per Indian codes, compressive strength of concrete is defined as: Field cured concrete in cubic steel molds (Greece) The compressive strength of concrete is given in terms of the characteristic compressive strength of 150 mm size cubes tested after 28 days (fck). In field, compressive strength tests are also conducted at interim duration i.e ...

  9. Types of concrete - Wikipedia

    en.wikipedia.org/wiki/Types_of_concrete

    Unlike air-entrained concrete, which introduces tiny air bubbles through an admixture during mixing, foam concrete replaces coarse aggregates with these air bubbles, resulting in a significant difference in density, with foam concrete typically ranging from 400 kg/m3 to 1600 kg/m3, whereas air-entrained concrete maintains its density. Foam ...