Significance and Use Compression tests provide information about
the compressive properties of plastic lumber and shapes when
these products are used under conditions approximating those
under which the tests are made. In the case of some materials,
there will be a specification that requires the use of this test
method, but with some procedural modifications that take
precedence when adhering to the specification. Therefore, it is
advisable to refer to that material specification before using
this test method. Table 1 in Classification D 4000 lists the
ASTM materials standards that currently exist. Compressive
properties include modulus of elasticity, secant modulus,
compressive strength, and stress at a given strain. In the case
of a material that fails in compression by a shattering
fracture, the compressive strength has a very definite value. In
the case of a material that does not fail in compression by a
shattering fracture nor exhibits a compressive yield point, the
compressive strength is an arbitrary