The Filton Bank 4 Track project increases the number of tracks from 2 to 4 between Dr Days and Filton Abbey Wood Station in Bristol. CAN was contracted to carry out a number of cutting and embankment earthworks projects to allow an increase in the width of the track bed over the scheme length.
At Filton Abbey Wood Station, CAN was contracted to construct a 45m long anchored contiguous piled concrete retaining wall.
The installation of 323mm dia bored piles was carried out by others; CAN then cropped the piles to expose the reinforcement to tie into a pile cap. Pile cap reinforcing steel and shuttering was installed by CAN. The pile cap (consisting of a 36m long upper pile cap and a lower 9m cap which accounted for the step in height over the length of wall) was poured in situ.
Once the capping beam concrete had been allowed to cure, CAN DTH drilled boreholes through pre-placed ducts in the pile cap into competent rock behind, and installed Dywidag DCP anchors . A total of 44No anchors were installed to 8m depth.
Following acceptance testing and loading of all the anchors, the full retained height of the wall was exposed in one excavation. CAN fixed reinforcing steel, pile drain and weep pipes and installed a bespoke formwork system. The wall was then poured in situ utilising mobile boom pumps, pouring the wall in 12m bays.
The works were completed safely, on time and to a very high level of quality.
Duration: 8 months
Location: Filton, Bristol
Other parts of the works included: