Examination of Degraded Aggregate Cement Value Test

The degraded ballast cement-test variables are investigated and a standardized test evaluated. The test data presented clearly show that the test, as previously specified by AREA or presently used by Amtrack, is not rigidly enough specified to allow repeatability between different laboratories. The method standardized herein is given in such sufficient detail that variability should be reduced to a minimum. Test data presented show that the cement strength test, used with the Mill test, is valuable in identifying those aggregates that need petrological evaluation including thin-section analysis. In addition, ballasts with low cement strengths were identified as having highly permeable fines, which is one of the qualities of superior ballasts.