Piled retaining walls have become common place, allowing basement construction to extend many storeys below ground level. Used as either temporary or permanent works, piled walls can provide high stiffness retaining elements affording large excavation depths with minimal disturbance to surrounding structures, properties or utilities.
Piling is a cost-effective way of forming a retaining wall, as there is reduced bulk excavation with maximum underground space. The Piles can follow complex layouts.
This method of piling creates a retaining wall to restrain the strata while excavations are carried out to form basements or to maximise the usable space on a site. Piles may form part of the permanent structure or be used solely for the temporary excavation stage. They can be designed as either free cantilever or propped.
This method offers the fastest and most efficient solution when short-term water retention is required, due to excavation below groundwater level. Primary piles are constructed with a pre-calculated gap between them, using a 'soft' cement-bentonite mix or 'firm' concrete.
Secondary piles, formed of structural reinforced concrete, are then installed between the primary piles, cutting into them on either side, with a typical interlock of 150mm., depending on the particular requirements of the project. They will generally keep a basement excavation reasonably dry for follow on construction works.