Rapid field test for carbonation of lime or cement treated materials

Abstract

A rapid field test for carbonation of lime, lime-slag, lime-pfa, cement, cement-pfa or cement-slag stabilized pavement material is described. The treated material is simply sprayed with phenolphthalein, phenol red and dilute hydrochloric acid solutions. If the untreated material does not contain carbonate (i.e., fails to effervesce with hydrochloric acid) and the treated material does not turn red with phenolphthalein, but turns red with phenol red and effervesces with hydrochloric acid, the material is carbonated. If the untreated material does contain carbonate (i.e., effervesces with hydrochloric acid and probably turns red with phenol red) and the treated material does not turn red with phenolphthalein, the material is probably carbonated. The phenolphthalein test can also be used to test for the presence or absence of lime or cement in a frehly treated material, but not for the amount present.