Use of Clegg hammer for compaction control

This report describes the use of the Clegg Impact Tester, nuclear gauge and sand cone equipment to obtain density of various types of soils in Indiana. The density data collected on various types of soils and B-borrow on selected contracts in Indiana were used to correlate the Clegg Impact Hammer with nuclear gauge and sand cone equipment. Statistical analyses indicated that the Clegg Impact Values are affected by many factors, such as moisture content, amount of sand, etc., in the soil. Those effects were not measured in this study. For this reason, the use of the Clegg Impact Tester to determine density of various soils in Indiana for the Indiana Department of Transportation is not recommended. Its use to check compaction of backfill materials in the "Type X" trenches is also not recommended due to problems testing the coarse granular backfill.