1.1 This test method provides an index to the expansion potential of compacted soils when inundated with distilled water.1.2 This test method controls variables that influence the expansive characteristics of soils and still retains a relatively simple test for practical engineering applications.1.3 The values stated in SI units are to be regarded as the standard. The values stated in inch-pound units are approximate.1.4 All observed and calculated values shall conform to