ASTM C1567-21 PDF Download

ASTM C1567-21 is a standard test method that allows for the evaluation of the potential alkali-silica reactivity (ASR) of combinations of cementitious materials and aggregate using the Accelerated Mortar-Bar Method. The test is specifically designed to assess the ability of pozzolans and ground granulated blast-furnace slag to control deleterious internal expansion caused by ASR when used with an aggregate intended for use in concrete.

The test method, developed at the National Building Research Institute in the Republic of South Africa, provides an empirical result that can be compared to criteria within specifications to determine the acceptance or rejection of the combination of materials for a particular application. However, it should be noted that currently there is no standard procedure for testing fine and coarse aggregates together in a single batch of mortar, nor for varying the proportions of the constituent materials beyond the relative proportions of the individual cementitious material constituents.

It is important to consider that the results obtained using this test method may overestimate the reactivity of certain aggregates if they are used in service with the same pozzolans or slag and hydraulic cement of low alkali content. Therefore, caution should be exercised in interpreting the results.

Different levels of pozzolan and ground granulated blast-furnace slag may require testing to determine the amount required to reduce expansion to an acceptable level. These materials can be tested separately or in combination.

It is recommended to also test the same aggregate and hydraulic cement (without pozzolans and slag) using Test Method C1260 in order to have a comprehensive understanding of their reactivity.

Lastly, it should be noted that this test method may underestimate the expansion of cementitious systems containing pozzolans with an alkali content higher than 4.0% sodium oxide equivalent. For such materials, Test Method C1293 is recommended for accurate assessment of their potential for deleterious reaction.