ASTM C1260

Full Name

ASTM C1260 – Standard Test Method for Potential Alkali Reactivity of Aggregates (Mortar-Bar Method)

Scope

ASTM C1260 outlines a test method to determine the potential alkali reactivity of aggregates intended for use in concrete. This reactivity, specifically alkali-silica reaction (ASR), can cause deleterious expansion and cracking in concrete structures.

The scope of ASTM C1260 includes:

  • Detecting potential reactivity: the test method aims to identify aggregates that have the potential to react with alkalis in cement, leading to ASR and subsequent damage to concrete.
  • Mortar-bar method: the test utilizes mortar bars prepared with the aggregate under investigation. These bars are subjected to an accelerated aging process in a highly alkaline solution at an elevated temperature.
  • Measuring length change: the length change of the mortar bars is monitored over a 16-day period. Excessive expansion indicates a potential for deleterious ASR.
  • Criteria for evaluation: the standard provides criteria for evaluating the potential alkali reactivity of the aggregate based on the measured length change. Aggregates are classified as potentially innocuous, potentially reactive, or requiring further testing.

Limitations: The standard acknowledges that the test is not a direct measure of the actual expansion that may occur in concrete. It is a screening test to identify aggregates that may require further evaluation or precautions in their use.

In summary, ASTM C1260 provides a standardized method for assessing the potential alkali reactivity of aggregates, helping to prevent the costly and damaging effects of ASR in concrete structures.

ASTM C1260 Accredited Laboratory

Applied Testing & Geosciences, LLC is accredited for performing tests using the ASTM C1260 standard.

Contact us for more information.

Resources

Keywords

alkali-silica reaction; mortar bars; aggregates; length change; expansion; alkali reactivity; deleterious expansion; sodium hydroxide solution; accelerated aging; potential reactivity