Effects of Salts on Road Embankment Stability under Freezing and Thawing Conditions

摘要

Frost heave test performed on a base course material as part of an earlier study indicated that the addition of 0.1% calcium chloride reduced heave by 50%, while 0.5% reduced heave by 95%. The gravel was of a type widely used in Interior Alaska for highway base and subbase materials. In response to this, a more detailed study was undertaken to assess the effects of salt on soil stability, principally frost heaving. Gravels from the original study source and others typical of Interior Alaska were used. The study found that frost heave effects due to salt varied widely with soil type and freezing conditions and could not be predicted using standard soil tests. It also indicated that little salt remains in a road section several years after application. It was concluded that the use of salt is probably not a practical or economical design alternative for increasing the frost stability of embankment materials.