Full Name

AASHTO T380 – Standard Method of Test for Potential Alkali Reactivity of Aggregates and Effectiveness of ASR Mitigation Measures (Miniature Concrete Prism Test, MCPT)


This test method allows detection of the potential for deleterious alkali-silica reaction of aggregate in miniature concrete prisms within 56 days (8 weeks) for most of the aggregates.

An additional 28 days (4 weeks) may be necessary in the case of low / slow reacting aggregates to assess their potential reactivity.

To assess the effectiveness of mitigation measures of SCMs (supplementary cementitious materials, such as fly ash, slag, silica fume, and others); the test method is conducted for 56 days.


aggregates; potential alkali reactivity; ASR mitigation; Miniature Concrete Prism Test; MCPT