Rotary bored piling

Rotary bored piling (RBP) uses a machine with specially designed drilling tools, buckets and grabs to remove soil and rock. With every four or five turns of flight, the auger is bored into the ground, withdrawn, and the spoil removed until the design depth is reached.

Shaky ground

Temporary or permanent casings can be used if the surrounding ground will not withstand this process. Casings are handled by the rig or by cranes, depending on their size and weight.

When large-scale assignments and those liable to flooding from groundwater prevent the use of casing a drilling fluid, such as bentonite, is used.

RBP benefits

The advantages of RBP over CFA piling are the depths and diameters achievable. Also, by using casing, an open hole can be formed to great depths. This enables chiseling or coring to form rock sockets, setting unusually long or complex reinforcement cages, or complex pile instrumentation and load cells.

RBPs deeper than 40m are common and recent trends have seen piles that are over 70m deep.

Last updated: 23/01/2017