For difficult access or low headroom sites small purpose built piling rigs can be employed. They use either rotary or continuous flight auger techniques to suit the prevailing ground conditions. Using such methods mini piles can be drilled in diameters from 200mm to 450mm and to depths of up to 20.0 metres.
The power pack for the rig is usually positioned remotely and connected to the rig by hydraulic hoses. This allows the actual drilling to be carried out in areas sensitive to noise and exhaust emissions.
The compact nature of the equipment allows access through a width of approximately 1.0 metre and drilling in headroom of approximately 2.6 metres.
Mini piles can have many uses including bearing piles and retaining wall piles. Their reinforcement can consist of traditional rebar cages lapped together, single bars or steel tubes. They can be formed with grout for the smaller diameters or concrete with 10mm aggregate for larger diameters.
