USE OF LIGHTWEIGHT DYNAMIC CONE PENETROMETER FOR COMPACTION CONTROL OF COHESIONLESS SOILS

Abstract

Evaluation of the adequacy of field compaction of granular soils, has always been a challenge for geotechnical engineers. The Lightweight Dynamic Cone Penetrometer (LDCP) has been established as one of the most versatile techniques, as it significantly reduces the required effort and cost. This research has been conducted to correlate the readings of LDCP laboratory tests, to compaction parameters of cohesionless soils. An experimental program has been performed on four different types of granular soils, at various compaction levels and moisture content values. The investigated soils included two sandy soils with different gradation and two different admixtures of sand with crushed dolomitic limestone. A series of LDCP and sand-cone tests have been conducted on soil samples which were compacted in a cubic steel mold, 60cm side length. The laboratory results have been integrated into a number of predictive correlations, which are capable of assessing the soil compaction parameters including; relative compaction, relative density, dry density and uniformity coefficient. Moreover, the compacted granular soils were found to be more sensitive to changes of moisture content from the optimum value, at lower ratios of relative compaction.