Project Gatwick

Project: Stabilisation of an existing 5m high failed gabion faced soil nailed slope with new soil nails and a new gabion facing.

Location: Redhill

Contract Duration: 7 weeks

Anchors Installed: 400

Area Treated: 400m2

Equipment: Excavator, excavator mounted drill mast, access platform and crane.

We were employed to stabilise an existing soil nailed, gabion faced slope that was failing due to water pressures in the sandy slope behind, which had not been identified by the contractor during the original design and installation.

The failed section of the existing gabion facing was removed and stabilised in sections. Each section of the slope was re-profiled and additional soil nails installed and a new geotextile membrane and structural mesh secured to the face and a series of weep-holes installed before a new gabion facing was constructed and tied in to the remaining sections of the existing face at either end of the works.

Sections of the facing were also extended in height to support the upper slope, where it had been left unprotected.

The existing facing had to be removed to the level of the existing footings, which were up to 1m below existing ground level before the new facing could be installed. The line of the new gabion facing had to be adjusted and stone placed behind the new facing to maintain the original line of the boundary slope.

Access and working hours were limited because the site formed the boundary to the gardens and car park of an existing residential development, which had to remain occupied throughout the works. There was also a service building adjacent to the slope and we arranged a crane to move and temporarily relocate the building whilst the remedial works were completed in this area.

Costs to the client were minimised by re-using as much of the original gabion stone as possible and the car parking area was protected to prevent any damage. The garden area was re-profiled ready for re-turfing on completion with no damage to any existing planting.