Technical specifications
- 18 no.
- Ø 900 mm
- 14 m long
Bored piles under low headroom
Thaumasite degredation to the pad foundations of a road bridge crossing the M5 motorway required 900 mm diameter piles to be constructed adjacent to live motorway and beneath the existing bridge in 5,5 m of headroom, and in between existing bridge columns.
The existing bridge had pad foundations separated by a gap between the columns. This allowed large diameter piles to support a new link beam replacing the degraded pad foundations.
The piling was completed on program, in several phases, allowing each existing overbridge pier to be replaced in sequence.
The Martello solution
Martello used their MP5000 series rigs to form 900 mm diameter piles to 14 m at locations between existing columns to support the overbridge through temporary works, allowing the existing degraded concrete foundations to be removed, and the existing bridge columns to be integrated with the new foundations provided by Martello.
This technique allowed the client to retain the existing overbridge whilst replacing the foundations, without causing disruption to the overbridge or the motorway.
The large diameter piles provided by Martello were critical to this process, by providing high capacity foundations, in locations inaccessible by conventional equipment.
