ASTM C580-18

4.1 This test method is generally applicable to rigid and semirigid materials. Although flexural strength cannot be determined for those materials that do not break, tangent modulus of elasticity can be determined.

4.2 The results obtained by this test method should serve as a guide in, but not as the sole basis for, selection of a chemical-resistant material for a particular application. No attempt has been made to incorporate into this test method all the various factors that may affect the performance of a material when subjected to actual service.

4.3 In addition to the tangent modulus of elasticity, a secant modulus is calculated at the point on the stress-strain (load-deflection) graph where the strain is 50 % of the maximum strain.

1.1 This test method covers the determination of flexural strength and modulus of elasticity in flexure of cured chemical-resistant materials in the form of molded rectangular beams. These materials include mortars, brick and tile grouts, structural grouts, machinery grouts, monolithic surfacings (60 mils or greater), and polymer concretes. These materials shall be based on resin, silicate, silica, or sulfur binders.

1.2 A bar of rectangular cross section is tested in flexure as a simple beam in center point loading: the bar rests on two supports and the load is applied by means of a loading nose midway between supports.

1.3 Method A outlines the testing procedure generally used for systems containing aggregate less than 0.2 in. (5 mm) in size. Method B covers the testing procedure generally used for systems containing aggregate from 0.2 to 0.4 in. (10 mm) in size. Method C is used for systems containing aggregate larger than 0.4 in.

1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.5 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.

1.6 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.