Correlations Among CPT, MPT, and SPT in Clayey Soils: A Case Study from Central Northern Algeria

Standard penetration test (SPT), cone penetration test (CPT), and Menard pressuremeter test (MPT) are common field tests used during site investigations to identify the different soil characteristics. Correlations among these tests are also used by practitioners as alternative tools to acquire additional geotechnical information at a low cost. Correlations of CPT–SPT and MPT–SPT are well-documented in the literature. However, applying the existing empirical models to different soil ranges and locations requires more caution. This research aims to propose correlations among CPT, MPT, and SPT for clayey soils of different consistencies ranging from low to high plasticity and degree of consolidation gathered from two sites in central northern Algeria. The database includes 76 boreholes with varying depths as well as disturbed and undisturbed soil samples for laboratory testing to identify soil type classification. Correlations were proposed separately for each site and all sites. As a result, nine (09) empirical equations are proposed in this study, providing a valuable resource for further analysis and exploration in this field. The accuracy of models was evaluated using the coefficient of determination (R-squared value) and the Fisher test (F test). The proposed models in this study were compared with those published in the literature using statistical metrics, namely the root mean square error (RMSE) and mean square error (MSE). Accordingly, the proposed correlations in this study are more reliable, confirming the importance of the research on the local correlations.