Soil‐Sheet Pile Interaction in Vibro‐Piling

The study of skin friction developed in the present article falls within the scope of research work on high‐frequency vibro‐piling (1,500 to 3,000 Hz). Our laboratory measurements performed thus far have concerned the general behavior of the test unit without dissociating point force and skin friction. Previous studies have indicated that vibro‐piling is only possible when an excitation frequency is used equal to one of the frequencies characteristic of the system. A more refined analysis of the phenomena involved depends on determination of the skin friction coefficient which was measured in our laboratory using a horizontal test bench. It was thus shown that this friction coefficient is a decreasing function of the power transmitted by the exciter to the sheet pile: it is directly related to the depth of penetration of the sheet pile into the sand; and it is independent of the forward movement velocity of the sheet pile without excitation but increases with this velocity in the presence of excitation, thereby enabling reconstruction of a vibro‐driving curve to provide satisfactory estimation of refusal.