Much has been made in the news lately about the controversial practice of infilling bridges with aggregate stabilized by lean mix concrete. The MARS System offers a much cheaper alternative for masonry arches, typically less than 50% of the financial cost of infilling and a small fraction of the environmental and ecological cost.
The MARS System offers a permanent, maintenance-free, solution in that it uses stainless steel bars fully encapsulated in an inert adhesive grout. It utilises the inherent strength of the arch barrel, so that only a minimum amount of material is added, and it is installed using handheld tools. No large plant is involved.
The true cost of infilling a bridge
The infilling solution entails local congestion, emissions and diesel usage from the transportation of heavy plant and many tons of aggregate and concrete. It necessitates the permanent loss to the planet from the quarrying and extraction of the aggregates and requires the generation of a huge amount of greenhouse gases from the manufacture of the cement used in the concrete mix. It also causes permanent disruption to the local ecosystems.
The benefits of the MARS system
The MARS System is installed from a raised platform underneath the bridge so there is minimum disturbance to flora and fauna and no disruption to users of the bridge.
Masonry arches are stabilised by the loads they carry and, when this loading is no longer applied, such as when rail routes are turned into walkways and cycle routes, then the compression in the barrel relaxes and bricks tend to fall out. The grid of encapsulated stainless-steel bars, pinned back into the barrel, prevents this. It typically only requires the installation of a nominal inexpensive MARS System for stabilisation.
The MARS System thus allows our rich heritage of masonry bridges to be preserved and enjoyed for future generations – unlike the infilling solution.
The photos below show the set-up of a MARS System working platform for a small bridge in Sheffield and the stabilisation of a redundant railway bridge over the river Wye. Most of the bottom ring of brickwork had fallen away. It was reconstructed and the bridge was stabilised using the MARS System. In this case, the working platform was suspended from the top of the bridge.
Building up a new brickwork ring on the redundant railway bridge.