scope:

These methods of test cover procedures for determining the soil-cement losses, moisture changes, and volume changes (swell and shrinkage) produced by the repeated wetting and drying of hardened soil-cement specimens. The specimens are compacted in a mold, before cement hydration, to maximum density at optimum moisture content using the compaction procedure described in T 134. 1.2. Two methods, depending on soil gradation, are covered for preparation of material for molding specimens and for molding specimens as follows:

Method A-Using soil material passing the 4.75-mm (No. 4) sieve. This method shall be used when 100 percent of the soil sample passes the 4.75-mm (No. 4) sieve. See Sections 4 to 6.

Method B-Using soil material passing the 19.0-mm (³/₄-in.) sieve. This method shall be used when part of the soil sample is retained on the 4.75-mm (No. 4) sieve. See Sections 7 to 9.

The values stated in SI units are to be regarded as the standard.

The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of R 18 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with R 18 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of R 18 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.