Volume stability expansion of steel slags

This test is used for steel slags to determine their susceptibility to expansion as a consequence of the hydration of free lime or free magnesium oxide. 

According to CEN EN 1744-1 (2009), paragraph 19.3, a compacted slag specimen is subjected to a flow of steam at 100 C in a steam unit at ambient pressure for 24 or 168 h (7 days) depending on slag type. 

Any change in volume, owing to the reaction of moisture with free lime or magnesium oxide, is recorded with the aid of a dial gauge. The result is expressed as a percentage increase of the volume in relation to the initial volume of the compacted sample. 

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