STANDARD TEST METHOD FOR POTENTIAL ALKALI REACTIVITY OF CARBONATE ROCKS FOR CONCRETE AGGREGATES (ROCK CYLINDER METHOD) (R 1986)
|Publication Date:||3 October 1969|
|ICS Code (Concrete and concrete products):||91.100.30|
This test method covers the determination of the expansive characteristics of carbonate rocks while immersed in a solution of sodium hydroxide (NaOH) at room temperature. The observable length changes occurring during such immersion indicates the general level ofreactivity of rocks and whether tests should be made to determine the effect of aggregate prepared from the rocks upon the volume change in concrete.
NOTE I-Alkalies participating in the expansive reactions usually are derived from cement; under certain circumstances they may be derived from other constituents of concrete or from external sources. Two types of alkali reactivity of aggregates are recognized: (1) an alkali-silica reaction involving certain siliceous rocks, minerals, and artificial glasses and (2) an alkali carbonate reaction involving dolomite in certain calcitic dolomites and dolomitic limestones. This test method is not recommended as a means to detect the first ofthese reaction types.
The test method is intended as a research screening method rather than for specification enforcement. It is intended to supplement data from field service records, petrographic examinations, and tests of aggregate in concrete.