Evaluation of calcareous base course materials stabilized with low percentage of lime in South Texas

Two base course materials commonly used in South Texas - limestone and caliche aggregate - were tested extensively to examine the effect of carbonate cementation due to the addition of small percentages of hydrated lime Ca(OH)2. Testing included mineralogical analyses of the two materials, strength analyses in terms of Texas triaxial strength, Atterberg limits testing, scanning electron microscopy examinations, and resilient moduli determinations of the materials in the laboratory and in the field. Caliche and limestone base materials stabilized with either 1 or 2 percent hydrated lime were compared to control (unstabilized) materials in terms of the analyses listed previously. In addition, the falling weight deflectometer was used to backcalculate the moduli values of the pavement layers using the program MODULUS. The addition of 1 to 2 percent calcium hydroxide significantly increased compressive strength, as measured by the Texas triaxial test, and significantly increased resilient modulus over a wide range of deviatoric stress states. These engineering property improvements (measured in the laboratory were verified in the field through falling weight deflectometer testing.

Evaluation of calcareous base course materials stabilized with low percentage of lime in South Texas Academic Article