This specification covers backer material, either in rod or strip form, for use with cold- and hot-applied joint sealant in portland-cement concrete or asphalt-pavement joints. Sealant backer material is available in three types: Type I, Type II, and Type III, and serves one or more of the following purposes: (1) limits the amount and depth of sealant applied to a joint, (2) acts as a barrier interface to prevent backside adhesion (bondbreaker), and (3) provides a form to assist the sealant in developing a shape factor. The material shall be easily compressed and installed in the joint reservoir and shall be heat resistant when used with hot-applied sealants. Physical properties of the material shall conform to the specified requirements for (1) density, (2) tensile strength, (3) water absorption, (3) compression deflection force, (4) compression recovery, (5) heat resistance, and (6) maximum shrinkage. The test specimen, test procedure, apparatus, and calculations for the physical properties enumerated are detailed.

1.1 This specification covers backer material for cold- and hot-applied joint sealant for use in portland-cement concrete or asphalt-pavement joints.

1.2 This specification establishes basic requirements for sealant-backer material either in rod or strip form, that can withstand the temperature of hot- or cold-applied sealants without excessive deformation.

1.3 Sealant backer material serves one or more of the following purposes:

1.3.1 Limits the amount and depth of sealant applied to a joint,

1.3.2 Acts as a barrier interface to prevent backside adhesion (bondbreaker), and

1.3.3 Provides a form to assist the sealant in developing a shape factor.

1.4 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information purposes only.

The following safety hazards caveat pertains only to the test methods described in this specification. 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.