Pressing

Pressing is used primarily when there are severe restrictions placed on noise and vibration. This is mostly the case in residential districts, very close to existing buildings and on embankments. In contrast to driving using impact hammers and vibration techniques, the sheet piles are simply forced into the ground using hydraulic pressure. Noise and vibration are therefore kept to a minimum. We distinguish between pressing plant supported from a crane, plant guided by a leader and plant supported on the heads of piles already driven.

In the first method, a crane lifts the pressing plant onto a group of piles which are then pressed into the ground by means of hydraulic cylinders (as the follow picture shows). To do this, the hydraulic cylinders are clamped to each individual sheet pile. At first, the self-weight of the pressing plant and the sheet piles themselves act as the reaction to the pressing force. As the sheet piles are driven further into the ground, it is increasingly the skin friction that provides the reaction. Both U- and Z-sections can be pressed, and the method can also be used to extract sheet piles.

20150915