Mapei has been specified for a capacity upgrade project with London Underground at Bank Station.

The upgrade required Mapei’s products for waterproofing, repairs to the concrete and masonry, a new construction and structural reinforcement.

Mapegrout Gunite FSD and the Mapelastic TU System were both specified for as they share the requirement of being packaged in a way that would minimise lifts during use in the tunnel shaft.

Mapelastic TU’s pre-mixed formula gets rid of dust whilst providing consistency between each layer when applying. The product is available in both green and white to ensure complete coverage of each layer is visible.

It offers a clean and neat application with no overspray proving to be useful at Bank Station due to the small passageway adits and tunnels.

One-component, fibre-reinforced cementitious mortar Mapegrout Gunite FSD was applied using a wet spray application, creating a thixotropic consistency for easy application on vertical and overhead surfaces. Its fast curing time allowed the installers and equipment to move through the tunnels quickly, improving the speed of application.

Due to the detailed specification and the parameters for completion, UTT (Underground Technology Team) Manager for Mapei UK, Steve Price developed and delivered training to operatives who required further technical assistance with the waterproofing system, specifically for the complex installation.

The training, consisting of two modules, was made up of a theory course examining the technical requirements for successful application, followed by a second module – the actual operation of equipment and application through to testing. This approach has resulted in the most successful application of underground waterproofing seen in the UK.