Experimental Investigation of Effective Parameters on the Results of Geotechnical Penetration Tests Using Manual Dynamic Penetrometer in Sand

Penetration tests are one of important geotechnical insitu tests by which, different soil parameters can be estimated. The advantages of these tests are easiness, high speed, and repeatability. In this research, a penetrometer called as “Manual Dynamic Penetrometer (MDP)” is utilized to perform tests on dry Firoozkuh Sand with three different relative densities. The MDP is similar to other penetrometers used in geotechnical engineering, but the dimension is different which causes to generate more power to penetrate into the soil with deeper layers. The aim of this research is to investigate the effect of cone geometry as well as applied energy on test results. To do so, three different cone diameters and cone apex are considered. In addition, the mass of the hammer is also changed in three different values. The comparison of results indicate that the come apex does not influence the penetration value; however, the cone diameter plays the role. It is also seen that the applied energy has direct relationship with the penetration. Since the mechanism of the cone penetration is similar to that of pile driving, it was also shown that it is possible to estimate the residual internal friction angle of the soil by using empirical formula proposed by Meyerhof.