How is soil tested to determine the proper amount of lime needed for stabilization?
Two ASTM procedures apply ASTM D-6276, Standard Test Method for Using pH to Estimate the Soil-Lime Proportion Requirement for Soil Stabilization and ASTM C-977 (Appendix A). The amount of lime, as a percentage of the soils bulk dry density, needed to maintain a pH level of the moistened soil-lime mixture of at least 12.4 for one hour is determined. Strength tests, generally unconfined compressive tests (ASTM D-5102) are then used to evaluate the long-term and weather resistance properties of the lime-stabilized soil.
