Effect of boundary conditions on dynamic cone penetrometer test

Abstract

This paper investigates the effect of boundary conditions on the Dynamic Cone Penetrometer (DCP) test. Two soil types e.g. sand and lateritic soil samples collected from a highway construction site were compacted in the metal molds having diameters of 150, 200, and 300 mm. These samples were prepared near the optimum moisture content using a modified compaction effort. Results indicated that the DCP penetration index (DPI) values obtained in varied mold diameters divided by the DPI values obtained in a 150-mm diameter mold increased as the ratio of mold-to-cone diameter increased for both sand and lateritic soil samples. This finding was also in good agreement with other study for a similar soil type. Caution must be exercised when testing the DCP in the metal mold due to the presence of boundary condition effect. The effect of boundary conditions on the DCP test on two soil types could be negligible.