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  2. Compressometer - Wikipedia

    en.wikipedia.org/wiki/Compressometer

    Compressometer for testing concrete stress-strain relation. A compressometer is a device used to determine the strain or deformation of a specimen while measuring the compressive strength of concrete specimens, generally a cylinder. It can be used for rock, [1] concrete, soils, [2] and other materials. For concrete, the device usually comprises ...

  3. Schmidt hammer - Wikipedia

    en.wikipedia.org/wiki/Schmidt_hammer

    The test hammer hits the concrete at a defined energy. Its rebound is dependent on the hardness of the concrete and is measured by the test equipment. By reference to a conversion chart, the rebound value can be used to determine the concrete's compressive strength. When conducting the test, the hammer should be held at right angles to the ...

  4. Arching or compressive membrane action in reinforced concrete ...

    en.wikipedia.org/wiki/Arching_or_Compressive...

    The derivation of the maximum arching moment of resistance of laterally restrained concrete bridge deck slabs utilised Rankin's [21] idealised elastic-plastic stress-strain criterion for concrete, valid for concrete cylinder strengths up to at least 70N/mm 2, which he had derived on the basis of Hognestad, Hanson and McHenry's [23] ultimate ...

  5. Compressive strength - Wikipedia

    en.wikipedia.org/wiki/Compressive_strength

    The characteristic strength is defined as the strength of the concrete below which not more than 5% of the test results are expected to fall. [ 16 ] For design purposes, this compressive strength value is restricted by dividing with a factor of safety, whose value depends on the design philosophy used.

  6. Properties of concrete - Wikipedia

    en.wikipedia.org/wiki/Properties_of_concrete

    Engineers usually specify the required compressive strength of concrete, which is normally given as the 28-day compressive strength in megapascals (MPa) or pounds per square inch (psi). Twenty eight days is a long wait to determine if desired strengths are going to be obtained, so three-day and seven-day strengths can be useful to predict the ...

  7. Cylinder stress - Wikipedia

    en.wikipedia.org/wiki/Cylinder_stress

    For the thin-walled assumption to be valid, the vessel must have a wall thickness of no more than about one-tenth (often cited as Diameter / t > 20) of its radius. [4] This allows for treating the wall as a surface, and subsequently using the Young–Laplace equation for estimating the hoop stress created by an internal pressure on a thin-walled cylindrical pressure vessel:

  8. Universal testing machine - Wikipedia

    en.wikipedia.org/wiki/Universal_testing_machine

    A universal testing machine (UTM), also known as a universal tester, [1] universal tensile machine, materials testing machine, materials test frame, is used to test the tensile strength (pulling) and compressive strength (pushing), flexural strength, bending, shear, hardness, and torsion testing, providing valuable data for designing and ...

  9. Types of concrete - Wikipedia

    en.wikipedia.org/wiki/Types_of_concrete

    High-strength concrete has a compressive strength greater than 40 MPa (6000 psi). In the UK, BS EN 206-1 [3] defines High strength concrete as concrete with a compressive strength class higher than C50/60. High-strength concrete is made by lowering the water-cement (W/C) ratio to 0.35 or lower.