A pile is driven to predetermined depth by the weight of a pile, and pressing down it during discharging of spoil by Earth Auger flight inserted in the pile hollow part.

An expansion bit or a high-pressure jet in order to provide a certain space for making bulb and injecting of root hardening slurry from the Earth Auger tip builds the expansion bulb more than pile diameter, bearing capacity is made to ensure with root hardening slurry.

Evaluation of bearing capacity by a load bearing capacity calculation formula, higher than a Pre-boring with root hardening cement slurry process.

This process is having economical, low vibration and low noise.

For application pile diameter 400-1000mm and the maximum pile length are about 110 times of pile diameter and 80m.

• 1Positioning the lower pile having hollow part, in which auger flights are inserted beforehand.
• 2Connect auger flights with the auger drive unit which is mounted on the leader of the piling rig.
• 3Rotate earth auger, boring the pile tip layer, and press down a pile during discharging the spoil from top of pile, with compressed air may useful generally.
• 4Connect a lower pile and an upper one after connecting auger flights in a lower pile with the ones in upper pile.
• 5Press and sinking down a pile to the predetermined depth in load bearing layer.
• 6Expanded foot is built in root by using the expandable auger head or high-pressure water jettingnd and injection of hardening slurry from an auger head is Performed.