Rotary Bored Minipiles
Rotary bored minipiles are suitable in most ground conditions; therefore, they are the most versatile regarding an engineer’s specification. These components are generally between 300mm and 750mm in diameter and installed using powerful high torque minipiling rigs typically weighing between 4.5 and 18 tonnes. They can be installed in restricted-access locations and low-headroom environments, depending on the rig and diameter requirements.
Rotary/auger bored minipiles are made using segmental augers that are rotated into the ground with the penetrated soil raised to the surface by the auger flights. Where the ground is unstable, a temporary casing can be installed in advance of the augers to maintain the stability of the pile bore and ensure no destabilisation of the surrounding soil occurs. When its predetermined design length has been achieved, the steel reinforcement is placed before it is filled with either concrete or grout. This technique is most effective in cohesive soils where minimal temporary casings are required, resulting in exceptionally quick and cost-effective installation.