A MECHANICALminipile system has been used to secure safety barriers and warning lights at a remote, unmanned level crossing in the Cambridgeshire Fens.
The barriers and lights of the railway crossing at Three Horse Shoes, near Peterborough, were threatening to topple over.
Repeated impact and vibrations as the barriers were raised and lowered was causing the concrete barrier bases to rotate backwards into the soft peaty soil.
Grundtuben was recently introduced to the UK by WT Anchor Systems. The hollow tube piles are driven to depth and an expansion tool inserted. This has mini hydraulic rams which force open the pre-split panels in the sides of the tubes at two levels to secure the piles in the ground. The piles are then filled with concrete.
Railtrack contractor Jackson Rail called in subcontractor Charterbuild to carry out stabilisation and install the Grundtuben as specified by WS Atkins.
A machine-mounted breaker took less than five minutes to drive each of four 4.8m long, 159mm diameter piles. Two were installed to the rear of each slab through the peat and into the underlying sandy loam. A groundbeam was then cast to connect the piles to the slab.
The piles were proof tested to tension loads of 20kN before the beam was cast.