What is Compressive Properties Testing?

The Compressive Property of a material is calculated as Psi required to rupture or deform a specimen in a given percentage of height. Several properties such as Strength, Pounds Force Applied and Models may be determined by use of this procedure.

1.1 The Compressive Properties Test method covers the determination of the mechanical properties of unreinforced and reinforced rigid plastics, including high-modulus composites, when loaded in compression at relatively low uniform rates of straining or loading. Test specimens of standard shape are employed.
1.2 The Compressive Properties Test values stated in SI units are to be regarded as the standard.   
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
3.1.1 Compressive Properties Test - compressive deformation-the decrease in length produced in the gage length of the test specimen by a compressive load. It is expressed in units of length.
3.1.2 Compressive Properties Test - compressive strain-the ratio of compressive deformation to the gage length of the test specimen, that is, the change in length per unit of original length along the longitudinal axis. It is expressed as a dimensionless ratio.
3.1.3 Compressive Properties Test -  compressive strength-the maximum compressive stress (nominal) carried by a test specimen during a compression test. It mayor may not be the compressive stress (nominal) carried by the specimen at the moment of rupture.
3.1.4 Compressive Properties Test - compressive strength at failure (nominal)-the compressive stress (nominal) sustained at the moment of failure of the test specimen if shattering occurs.
3.1.5 compressive stress (nominal)-the compressive load per unit area of minimum original cross section within the gage boundaries, carried by the test specimen at any given moment. It is expressed in force per unit area.
3.1.5.1 Discussion-The expression of compressive properties in terms of the minimum original cross section is almost universally used. Under some circumstances the compressive properties have been expressed per unit of
prevailing cross section. These properties are called "true" ! compressive properties. j
3.1.6 compressive stress-strain diagram-a diagram in which values of compressive stress are plotted as ordinates against corresponding values of compressive strain as abscissas.
3.1.7 compressive yield point-the first point on the I stress-strain diagram at which an increase in strain occurs I
without an increase in stress. '
3.1.8 compressive yield strength-normally the stress at the yield point (see also 3.11).
3.1.9 crushing load-the maximum compressive force applied to the specimen, under the conditions of testing, that produces a designated degree of failure.
3.1.10 modulus of elasticity-the ratio of stress (nominal) to corresponding strain below the proportional limit of a material. It is expressed in force per unit area based on the average initial cross-sectional area.
3.1.11 offset compressive yield strength-the stress at which the stress-strain curve departs from linearity by a specified percent of deformation (offset).
3.1.12 percent compressive strain-the compressive deformation of a test specimen expressed as a percent of the original gage length.
3.1.13 proportional limit-the greatest stress that a material is capable of sustaining without any deviation from proportionality of stress to strain.