【国外标准】 Standard Test Method for Determining Thermoplastic Pipe Wall Stiffness

5.1 The performance under bending and compression load of a thermoplastic plastic pipe wall design obtained by this method can be used for the following:5.1.1 To determine the stiffness of the pipe wall section. This is a function of the pipe dimensions, the wall design, the arc length tested, and the physical properties of the material of which the pipe is made.5.1.2 To compare the characteristics of various thermoplastic pipe wall designs.5.1.3 To compare the characteristics of various plastics in pipe form.5.1.4 To study the interrelations of dimensions, materials, and deformation properties of thermoplastic pipe designs.5.1.5 To measure the deformation and load-resistance at any of several significant events which may occur during the test.5.1.6 To provide a reasonable quality control/quality assurance test for very large diameter plastic pipes.5.2 The time-dependent pipe wall stiffness of a thermoplastic pipe obtained by this test method may used for the following:5.2.1 To predict the residual stiffness of the pipe wall in bending and compression at all times after initial loading.5.2.2 For purposes of design, to determine a modulus of relaxation under sustained loads.5.2.3 To quantify the influence of material formulations of thermoplastics on the modulus of relaxation.5.2.4 To study the influence of geometric patterns of wall profiles on the modulus of relaxation.5.3 The time-independent reduction of wall thickness at springline may be used for the following:5.3.1 For pipe wall stiffness, to quantify the efficiency of all wall profiles of any material composition and a given geometry with that of a solid uniform thickness wall.1.1 This test method covers the determination of the load-deflection behavior of thermoplastic pipe wall sections under parallel plate loading conditions.NOTE 1: These are not full pipe section tests, but pipe wall segment tests. The results of these tests will be different from pipe stiffness tests per Test Method D2412, although they may be proportional. This test provides quite different information, including stress relaxation under constant strain, and comparisons of the function and stiffness of different pipe wall designs or materials.1.2 This test method covers a loading test for determining the wall stiffness of a thermoplastic-pipe wall under a combined load of bending and compression. Changes in pipe wall profile geometry under load may also be determined.1.3 This test method covers thermoplastic pipe.1.4 The characteristics determined by this test method are wall stiffness and changes in profile wall dimensions at specific deformations.1.5 The characteristics determined by this test method are wall stiffness, profile wall efficiency, and for some wall elements stability at specific Strain levels.1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.7 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the specification.1.8 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.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.