MOISTURE AND DENSITY DETERMINATION. THROUGH RADIO-ACTIVE ISOTOPES

Abstract

o ensure adequate staoilityt the subgrade should •oe thoroughly compacted when the soil is at a favourable moisture content. The subgrade must not be all to become too wet during preparation and compaction. There is an optimum value of moisture content which should be maintained during the compaction to obtain maximum density th ere-by, best compaction ' for a particular sub-,grad e• To have proper control over that moisture value, frequent field checks should be applied during the construction invaiving wee our ero eat of moisture content and density. The available traditional methods of determining density and moisture content. (Proctors test or Modified 11*.A•5•ii906 test and oven•dry method) are very useful' as check but they can be of no help in controlling construct-ion, as the layer from which the sample was taken would. be buried by other layers by the time the result is known i. a. they are time consuming and complicated. The investigation of a non-destructive method of test-ing with the use of liadio..isotopest is therefore undertaken in this project to provide a quick and fairly accurate determination of the density and moisture content, required in the field compaction control of the sub-grade soils. 8