This 3.5m high road embankment affected by scouring and flooding resulted in some shallow sliding of the bank face inducing cracks in the adjacent footway and bus lay-by. Furthermore, a potential deep seated failure could compromise the safety of the road users above.
Given the site constraints a sheet piling solution driven to 8m depth had been favoured as a permanent solution. In the interim, we were contacted for a temporary solution. Our Geotechnical Team reviewed the project details and offered the specified temporary solution but also proposed an alternative 120 year design solution making sheet piling redundant.
The proposed hybrid design was executed in two phases. Firstly, a top-down construction secured the bank with anchors. Secondly, a bottom-up construction entailed building the bank face with reno mattress (toe) followed by two lifts of rock filled gabion baskets and then 7 layers of stone filled geocells. The gabion baskets and geocells were tied to the bank by coupling up with the anchor and load plates terminating within the baskets and geocells. Finally, geocells were filled with seeded topsoil promoting a green and aesthetically pleasing view.