myGeobrugg
2024
The slopes at Long Ashton, on the approach to Flax Bourton Tunnel, presented a significant risk to railway operations. Previous rock failures had occurred in the area, and with the main line running directly below the unstable sections, a permanent stabilisation solution was required to ensure the safety and reliability of the route.
Mercia Mudstone
Steep rock faces above the railway represented the highest risk to stability. These slopes were unstable and prone to movement, creating overhangs and threatening the railway below. To secure them, we installed rock bolts together with surface mesh, which stabilised the exposed rock and ensured long-term safety.
Further away from the tunnel, the ground conditions changed to softer deposits. In these areas, we reinforced the slopes using soil nails combined with high-strength mesh. This approach provided reliable protection while adapting to the different materials present on site.
We also refined the design for the lower slopes to reduce work during rail possessions. Instead of installing additional rows of nails, we used tight-fitting drapery netting. This adjustment significantly reduced installation time and costs while still providing the required level of safety.
Alongside the engineering works, we included measures to enhance biodiversity. Due to the presence of dormice, vegetation clearance was minimised. Where planting was possible, new native hedgerows were introduced, and log pile habitats were created from felled trees, supporting local wildlife and adding ecological value to the project.
영국
Railway
GEOBRUGG SUPERCOATING