Homogeneous unit delineation for interpreting dynamic cone penetrometer measurements

The current investigation is concerned with the homogeneous unit delineatio n procedure for pavements and subgrade soils using dynamic cone penetromete r (DCP) data as widely employed in the evaluation of the pavement structure components. For the purposes of highlighting statistically homogeneous gro ups of the measurements along the registered DCP data profile, the conventi onal (AASHTO) cumulative difference approach procedure has been applied to the profile of DCP characteristic values. The delineating procedure shows s ignificant sensitivity to the existing change in the mean value levels of t he DCP measurements. Analysis of the procedure application to the profile o f the DCP characteristic values (Penetration Index) and to the original num ber-of-blows values recorded during the DCP test has been done. The approac h simplifies application of the AASHTO delineating procedure when using the original number-of-blows data during the DCP test. The approach produces t he boundary position indication for the specific DCP characteristic profile s. Penetration characteristics for the delineated units have been used for predicting the California Bearing Ratio (CBR) parameter. The approach has b een supported by Microsoft Excel spreadsheets for the semi-automated analys is of the DCP data and application of the delineation procedure.