Secant Walls

Brompton Square

The Brompton Square project required a secant wall and load bearing piles to be constructed for a basement swimming pool and garaging in Knightsbridge London.

The wall required 600 and 750mm diameter piles with temporary casings up to 14 long. Particular attention had to paid to a listed arch within one meter of the wall, the existing terraced houses and a listed garden wall.

In order to maximise the floor plan or the basement it was necessary to position the centre line of the piles just 600mm from the house wall.

The bearing piles were constructed from existing ground level to save programme time and avoiding the necessity to lift a rig in to the basement. These piles were heavily reinforced to resist the tension loads when the basement was subsequently excavated.

Manchester Metro-link

The new Metro-link in Manchester was to be constructed through to the Sports City Stadium, the home of Manchester City F.C. The Metro-link was to run next to, and several metres below an existing canal, requiring a hard / hard secant wall, to retain the canal. Martello Piling were employed to construct the secant wall and a contiguous bored pile wall, where the Metro-link was to pass underneath the link bridge servicing the stadium. Martello Piling employed 2 of their MP5000 series machines, working in 4.0m of headroom, constructing 900mm diameter secant piles and 750mm diameter contiguous piles to depths of 10.0m. The pile reinforcement was installed in short sections of 2.5m and coupled together, and all the piles were constructed by tremie technique, at an output of approximately 1 pile per day. The MP5000 series rigs were ideally suited to this contract, being the only rigs able to construct piles of 750mm and 900mm in these conditions.

Latest Projects >>

Gerrards Cross

Lord Hills Bridge

Stabilization of the ground underneath the Lord Hills Bridge.

Gerrards Cross

Gerrards Cross

Restricted access problem overcome in construction of bored pile wall.



Reconstruction of the railway bridge undertaken after heavy flooding.

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