Auger bored piles 150mm dia to 300mm dia

Augered piles are formed using small tracked machines which use sectional flight augers normally in 1M sections to drill at the subsoil to give an open bore.

The final load capacity is dependant on the depth of the pile, the diameter of the bore and the shear strength and bearing strength of the soil. These piles are often formed with a heave sleeve in the top section to alleviate the effects of ground heave common in clay soils.

A high slump sulphate resisting concrete is used with full length reinforcement.

Retaining wall construction can employ bored piling techniques - normally CFA or rotary. They provide special advantages where available working space dictates that basement excavation faces be vertical. Both methods offer technically effective and cost efficient temporary or permanent means of retaining the sides of bulk excavations even in water bearing strata.

When used in permanent works, these walls can be designed to accommodate vertical loads in addition to horizontal moments and forces.

Construction of both methods is the same as for foundation bearing piles. Continuous walls are constructed with small gaps between adjacent piles. The size of this space is determined by the nature of the soils.