Technical Specifications
Secant pile wall made of CFA piles
LDP Rotary Bearing Piles
Relic piles removal
- Diameters: 600, 750, 900 & 1200 mm
- Depth: up to 40 m
The Challenge
To install a CFA/rotary piled secant box and bearing piles to facilitate the construction of a new mixed use development in Lavington Street, London.
The site had previously been piled with no confirmed detail of the piles that were previously installed. These piles clashed in multiple locations along the line of the secant wall and bearing piles.
Due to the Secant dig extending to the full limits of the Timber Square project, there was a requirement for a top down construction sequence in one area of site to allow loading bays without disruption of Lavington street by construction traffic.
The Solution
Over the duration of the project a Bauer BG30, BG33 and Soilmec SR45 piling rigs were used to carry out the piling works.
Reinforced concrete and sheet pile removal was carried in over 30 locations with the Bauer rotary rigs and the use of specialist tooling and equipment to allow the construction of the secant wall in its designed position without loosing valuable basement space for the development.
Franki used there own developed and manufactured adjustable plunge column frame to construct 10 plunge column piles with strict tolerances to allow for a top down slab to be constructed and provide access for vehicles within the site whilst basement construction is ongoing.
A 750mm and 620mm secant wall was constructed around the perimeter of the project with the use of both CFA and rotary rigs.
A series of temporary cased 750mm bearing piles were constructed with a low cage level to the same specification supplied by the designers to provide a uniform settlement for the projects cores. These piles were constructed with the use of 12M of temporary segmental casing and bored up to 30M deep.
