ASTM D6108-03

Standard Test Method for Compressive Properties of Plastic Lumber and Shapes

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. For many materials, there may 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 one depending upon the degree of distortion that is regarded as indicating complete failure. Many plastic lumber materials will not exhibit a true yield point. Compressive strength can have no real meaning in such cases. For plastic lumber, the stress at a given strain of 3 % (0.03 in./in. [mm/mm]) is typically used.  
Compression tests provide a standard method of obtaining data for research and development, quality control, acceptance or rejection under specifications, and special purposes. The tests cannot be considered significant for engineering design in applications differing widely from the load-time scale of the standard test. Such applications require additional tests such as impact, creep, and fatigue.
SCOPE
1.1 This test method covers the determination of the mechanical properties of plastic lumber and shapes, when the entire cross-section is loaded in compression at relatively low uniform rates of straining or loading. Test specimens in the "as-manufactured" form are employed. As such, this is a test method for evaluating the properties of plastic lumber or shapes as a product and not a material property test method.
1.2 Plastic lumber and plastic shapes are currently made predominantly with recycled plastics. However, this test method would also be applicable to similar manufactured plastic products made from virgin resins, or where the product is non-homogenous in the cross-section.
1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.
1.4 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.
Note 1—There is no similar or equivalent ISO standard.

General Information

• Status: Historical
• Publication Date: 09-Mar-2003
• ICS: 83.140.01 - Rubber and plastics products in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.20 - Plastic Lumber

Relations

• Replaces: ASTM D6108-97 - Standard Test Method for Compressive Properties of Plastic Lumber and Shapes
• Effective Date: 10-Mar-2003
• Replaced By: ASTM D6108-09 - Standard Test Method for Compressive Properties of Plastic Lumber and Shapes
• Effective Date: 01-Sep-2009
• Referred By: ASTM E2954-15(2022) - Standard Test Method for Axial Compression Test of Reinforced Plastic and Polymer Matrix Composite Vertical Members
• Effective Date: 10-Mar-2003
• Referred By: ASTM D7568-23 - Standard Specification for Polyethylene-Based Structural-Grade Plastic Lumber for Outdoor Applications
• Effective Date: 10-Mar-2003
• Referred By: ASTM E2925-19a - Standard Specification for Manufactured Polymeric Drainage and Ventilation Materials Used to Provide a Rainscreen Function
• Effective Date: 10-Mar-2003
• Referred By: ASTM D6111-19a - Standard Test Method for Bulk Density And Specific Gravity of Plastic Lumber and Shapes by Displacement
• Effective Date: 10-Mar-2003
• Referred By: ASTM D7258-23 - Standard Specification for Polymeric Piles
• Effective Date: 10-Mar-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D6108–03
Standard Test Method for
1
Compressive Properties of Plastic Lumber and Shapes
This standard is issued under the fixed designation D 6108; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope* D 6111 Test Method for Bulk Density and Specific Gravity
4
of Plastic Lumber and Shapes by Displacement
1.1 This test method covers the determination of the me-
5
E 4 Practices for Load Verification of Testing Machines
chanical properties of plastic lumber and shapes, when the
E 83 Practice for Verification and Classification of Exten-
entire cross-section is loaded in compression at relatively low
5
someters
uniform rates of straining or loading. Test specimens in the
E 691 Practice for Conducting an Interlaboratory Study to
“as-manufactured” form are employed. As such, this is a test
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Determine the Precision of a Test Method
method for evaluating the properties of plastic lumber or
shapes as a product and not a material property test method.
3. Terminology
1.2 Plastic lumber and plastic shapes are currently made
3.1 Definitions:
predominantly with recycled plastics. However, this test
3.1.1 compressive deformation—the decrease in length pro-
method would also be applicable to similar manufactured
duced in the gage length of the test specimen by a compressive
plastic products made from virgin resins, or where the product
load. It is expressed in units of length.
is non-homogenous in the cross-section.
3.1.2 compressive strain—the ratio of compressive defor-
1.3 The values stated in inch–pound units are to be regarded
mation to the gage length of the test specimen, that is, the
as the standard. The values given in parentheses are for
change in length per unit of original gage length along the
information only.
longitudinal axis. It is expressed as a dimensionless ratio.
1.4 This standard does not purport to address all of the
3.1.3 compressive strength—the maximum compressive
safety concerns, if any, associated with its use. It is the
stress (nominal) carried by a test specimen during a compres-
responsibility of the user of this standard to establish appro-
sion test. It may or may not be the compressive stress
priate safety and health practices and determine the applica-
(nominal) carried by the specimen at the moment of rupture.
bility of regulatory limitations prior to use.
3.1.4 compressive stress (nominal)—the compressive load
NOTE 1—There is no similar or equivalent ISO standard.
per unit area of minimum (or effective as calculated in
accordance with Test Method D 6111) original cross section
2. Referenced Documents
within the gage boundaries, carried by the test specimen at any
2.1 ASTM Standards:
given moment. It is expressed in force per unit area.
2
D 618 Practice for Conditioning Plastics for Testing
3.1.4.1 Discussion—The expression of compressive stress
2
D 883 Terminology Relating to Plastics
in terms of the minimum original cross section is almost
D 4000 Classification System for Specifying Plastic Mate-
universally used. Under some circumstances the compressive
3
rials
stress has been expressed per unit of prevailing cross section.
D 5033 GuidefortheDevelopmentofStandardsRelatingto
This stress is called the “true compressive stress”.
4
the Proper Use of Recycled Plastics
3.1.5 compressive stress-strain diagram—a diagram in
D 5947 Test Methods for Physical Dimensions of Solid
which values of compressive stress are plotted as ordinates
4
Plastics Specimens
against corresponding values of compressive strain as abscis-
sas.
1
This test method is under the jurisdiction ofASTM Committee D20 on Plastics 3.1.6 compressive yield point—the first point on the stress-
andisthedirectresponsibilityofSubcommitteeD20.20onPlasticProducts(Section
strain diagram at which an increase in strain occurs without an
D20.20.01).
increase in stress.
Current edition approved March 10, 2003. Published April 2003. Originally
approved in 1997. Last previous edition approved in 1997 as D 6108 - 97.
2
Annual Book of ASTM Standards, Vol 08.01.
3 5
Annual Book of ASTM Standards, Vol 08.02 Annual Book of ASTM Standards, Vol 03.01.
4 6
Annual Book of ASTM Standards, Vol 08.03. Annual Book of ASTM Standards, Vol 14.02.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D6108–03
3.1.7 modulus of elasticity—the ratio of compressive stress strain. In the case of a material that fails in compression by a
(nominal) to correspo
...