A CORRELATION ANALYSIS OF SHEAR PARAMETERS OF PLASTIC CLAY DETERMINED FROM DIRECT SHEAR AND TRIAXIAL SHEAR TESTS

In this research, the main objective is to establish the correlation function between the shear strength parameters of plastic clay obtained from Direct Shear (DS) test and the Triaxial Shear (TS) test. For this, hundred soil samples collected from the deltas of major rivers of Vietnam including Mekong River Delta in the South and Red River Delta in the North were analyzed and shear strength parameters (c and φ) were determined by TS test and DS test. Standard correlation coefficient was used to validate the degree of correlation of shear parameter variables. Results show that the degree of correlation of the analyzed variables is very high (R > 0.9) in between TS test and DS test. Thus, correlation function obtained from this study can help in the selection of appropriate laboratory method for determining ‘c' and ‘φ ‘ values of plastic clay of Vietnam deltas for the stability analysis of foundations of civil engineering structures in coastal plains.