Urban Bridge Widening and Retaining Wall Design A237 London Road

A hybrid retaining wall system was implemented, combining Maccaferri Green Terramesh reinforced soil slopes with a concrete panel retaining wall. The design incorporated 70-degree Green Terramesh reinforced slopes on three sides of the approach ramps, while a vertical concrete panel wall was used where space limitations required a more compact solution.

In total, 240 metres of Green Terramesh retaining wall were installed, reaching heights of up to 8 metres at the railway crossing. This reinforced soil solution provided the required steep slope stability while enabling rapid construction within a tight programme.

To minimise traffic disruption, the construction was carefully phased. The northbound retaining walls were completed first, allowing traffic to continue flowing, before switching to the southbound side with managed one-way traffic systems.

A key advantage of the Green Terramesh system is its ability to support vegetation growth. During installation, the topsoil behind the facing units was seeded with a selected vegetation mix. This allowed rapid establishment of greenery, creating a natural, environmentally sensitive finish. Over time, the structure has blended into the surrounding landscape, becoming largely concealed beneath vegetation.

The project successfully delivered a bridge widening solution that met structural, environmental, and logistical requirements. The use of Green Terramesh reinforced slopes provided a sustainable retaining wall system that combined engineering performance with aesthetic value, while minimising disruption in a busy urban setting.

A hybrid retaining wall solution comprising 70-degree Maccaferri Green Terramesh reinforced slopes to three of the approach ramp faces and one concrete panel-faced wall where space restrictions required a vertical structure. A total length of 240m Green Terramesh wall was installed to a maximum height of 8m where the bridge crossed the railway line.

The Green Terramesh reinforced slopes provided the required steep-faced green solution and were straightforward to install within the tight construction schedule. Traffic disruption was kept to a minimum by first completing the north-going walls before commencing the south-going and switching one-way traffic lanes accordingly.

During the installation of the embankment walls, the topsoil wedge behind the face of the Green Terramesh embankment was impregnated with a selected seed mix and vegetation rapidly established to an extent where the structure is barely visible beneath the natural cover.