ASTM D8329-20

5.1 Hydration is a critical aspect of GCCM installation. GCCM installations are often hydrated with excess water to ensure that a saturated condition exists. Therefore, it is not generally possible to monitor and control exactly the water addition that absorbs and hydrates the cementitious materials due the practical methods of hydration in use.

5.2 It is important to be able to distinguish the quality of cementitious material used in applications for GCCMs. A measurement of compressive strength properties of the cementitious material is often an accepted method to provide a measure of the cement strength and quality. The compressive strength properties will vary with the water/cementitious material ratio and, therefore, it is necessary to determine a practical value that approximates in-use hydration and not a water/cementitious material ratio that simply provides the maximum properties but cannot be expected as representative of actual use conditions.

5.3 The compressive strength of the cementitious material can be affected by both over and under hydration.

5.4 This method identifies a means to obtain a water/cementitious material ratio representative of that obtained by proper hydration of GCCMs to allow replication for laboratory compressive strength testing for use by GCCM designers, inspectors, and installers.

1.1 The purpose of the proposed test method is to obtain a water/cementitious material ratio that allows for a practical measurement of the compressive strength of the cementitious material contained within a geosynthetic cementitious composite mat (GCCM). This water/cementitious material ratio should be generally representative of that achieved practically upon the hydration of a GCCM. Because GCCM materials do not involve mixing or the use of exact water hydration methods when employed in the field, this method is necessary to provide a quantitative estimate of the water/cementitious material ratio.

1.2 This procedure determines the water/cementitious material ratio for a properly hydrated GCCM, which is then used to create cube or cylinder specimens for compressive strength testing as per the appropriate referenced ASTM test methods. Compressive strength results will then be representative of the strength of the inherent cementitious material found in the GCCM after normal GCCM hydration.

1.3 The values in SI units are to be regarded as standard. Values in inch-pound units are in parentheses for information.

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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 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.