Comparison of pressuremeter and plate loading results to determine the deformation modulus in fine-grained soil.

The pressuremeter test (PMT) and plate load test (PLT) are principal in-situ experiments for measuring soil stiffness and deformation parameters. Although the PLT can be costly and complicated at great depths the PMT can be easily done in a borehole. Empirical equations linking the parameters from these tests can be useful for cross-checking the parameters obtained by the two methods and can reduce costs. In the present study, PMTs and PLTs were carried out on fine-grained soil from two sites in Iran. The pressuremeter modulus (EPMT) and limit pressure (PL) from the PMT and plate load modulus (EPLT), subgrade reaction modulus (K) and reload modulus (Er) from the PLT were determined and the relationships between them were investigated. A reliable and significant statistical model for these empirical equations has been was proposed. It was found that the average EPMT was about 25% higher than that of the EPLT and an exponential relationship could be determined linking the parameters at each site. A logarithmic relationship has been proposed between Er and EPLT. The mean absolute percentage error (MAPE) for calculation of the EPLT, K and Er for both sites was less than 15.14, indicating that the proposed equations estimated their values with good accuracy. Comparison of data from PLTs and PMTs in another area recorded a MAPE of less than 13.08. [ABSTRACT FROM AUTHOR]