First sheet pile install process

I didn’t manage to record the very first pile installation, but I captured the second. In this short clip, you can see the drill rig vibrating a 7m-long sheet (5mm thick) into the sandy soil beneath.

As the contractors progress, they pause to check the sheet is plumb and straight. They also adjust the rig slightly laterally to keep the sheet aligned. The goal is to install each sheet as true and square as possible relative to the last one.

Once the sheet is mostly in place, the team removes the safety chains. This allows the sheet to be vibrated further down.

You’ll also notice how each sheet overlaps the previous one—using the fold in the pan of the sheet along the edge. It’s a bit like fingers interlocking in a “monkey grip.”

Final vibration down to the Reduced Level (RL)

In the next video, the excavator vibrates the sheet piles down to the required Reduced Level (RL).

A couple of the sheets were vibrated lower than the others. After that, those sheets were brought back up to about 600mm higher than the position shown.

Although the lower position is the actual height we need for the external works later on, we left the sheets higher to protect the fence footing line. Leaving them at this higher level also creates a small pathway across the site. After we add roadbase and level it out, site access from the front to the back becomes much easier—without people needing to walk through the active building area.

When we reach the external works stage, we’ll cut off the extra height using an oxy torch and bring everything back down to the final finished RL.

Excavator with sheet piling vibration head (limited access installation)

In this final video, you can see the end of a 30T excavator fitted with a vibration head.

This setup was used here because the normal piling rig head size, along with the hydraulic lines, would have fouled against the brick columns, capitals, and the fence line/gardens. In other words, it couldn’t move past the obstructions safely or effectively.

To work around that, the curved vibration head helps with alignment and provides the clearance needed. That allowed the team to attach properly to the sheet and vibrate it down to the required RL.

One more thing to note: before the vibration head is released from the sheet, the operator can vibrate the sheet both up and down. Once the sheet is resting, soil friction against the sheet increases. That means when they start again, the operator needs enough vibration force to overcome those holding forces and move the sheet through the soil again.

That’s why the initial vibration is usually the loudest—more force is needed to get the installation started.