In October 1986, the Transportation Research Program of the University of Kentucky published a report evaluating the addition of hydrated lime to the subgrade soils of Section 19 of the Ashland-Alexandria (AA.) highway (1). That study involved laboratory testing only and concluded that the engineering properties of these subgrade soils were significantly improved with the addition of 6 percent (by weight) hydrated lime. It was decided to add hydrated lime to the subgrade soils on Section 19.

Because that procedure had not previously been used in Kentucky, a study was approved to monitor construction procedures and the performance of an experimental section. The objectives were:

  1. photo documentation and monitoring of construction procedures;
  2. laboratory testing of subgrade samples for, freeze--thaw durability, triaxial and unconfined compressive strength, and resilient modulus;
  3. annual pavement coring and testing as listed in Item 2; and
  4. a construction report upon completion of construction and annual memorandum reports for five years.

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The contents of this report reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky or the Kentucky Transportation Cabinet. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names and tradenames are for identification purposes and are not to be considered as endorsements.