The detail

The total construction programme was approximately £8m with the geotechnical works valued at circa £3m. Innovation was required to support the exposed rock face beneath the Viaduct foundations, whilst also restricting movements to negligible levels during the construction phase, which was a key Network Rail requirement.

Our intelligent solution utilised pre-stressed rock anchors, with a near vertical hard shotcrete facing. The retaining structure was then covered by mass concrete, to protect against vehicle impact and corrosion. The anchors were installed using a detailed construction sequence, employing vertical and horizontal excavation in distinct bays. In partnership with designers Mott McDonald, we value engineered the original SMBC outline design, resulting in substantial cost savings through the replacement of 225m of retaining walls, equating to 60% of the project’s original retaining walls.