Retaining wall specialists, Maccaferri came up with a novel solution to enable the construction of apartment blocks on an undulating site in Monaghan town centre, Northern Ireland.
06/09/2007
Freeing up space for the buildings involved making an 18 metre-deep cut into a hillside adjacent to the site. While major ground works were clearly required, the cost of building one large retaining structure with substantial ground anchorage would have been prohibitive.
Instead, Maccaferri, proposed a novel composite solution in which the bottom part of the wall would be built to a height of nine metres using MacWall Landmark, segmental retaining walling. The wall would then be capped with a nine metre tall Maccaferri Terramesh reinforced earth system.
As well as the significant cost advantages of adopting this approach, it would also be much faster to build, enabling construction of the apartments to get underway much sooner.
Having received the go-ahead, the contract for building the structure was awarded to a local recommended installer, Derry-based Joe Kerlin Site Services.
According to Joe, health and safety was a major consideration in building a wall of this size. “From this point of view alone, the MacWall system was really the only alternative. Given the height of the cut into the hillside there would have been a real danger to workmen if, for example, a shuttered wall had been used,” says Joe.
“We were able to construct the 500m2 wall in around two weeks. A comparable shuttered wall on the other hand would probably have taken as long as two months to build.
“This meant that work on the apartment blocks was able to start much sooner than would have otherwise been possible. And because no sheet piling or shuttering was required it was by far the most economical solution,” adds Joe.
Given the scale of the project, the composite approach was also much more aesthetically pleasing than a traditional full height retaining wall.
The textured finish, careful colour blends and staggered laying pattern of MacWall Landmark provide an attractive, natural finish making it ideal for use close to residential developments. As well as its good looks, MacWall Landmark also provides high performance under extreme loading conditions through the system’s innovative positive mechanical connection between the EnkagridTMPRO reinforcement and the block which maximises the design strength. MacWall Landmark holds BBA Roads & Bridges accreditation and has been approved by the highways authority for use in structures requiring Northern Ireland’s TAS approval.
Achieving the desired look was also helped greatly through the use of Green Terramesh whose front face and geogrid anchorage elements are made from one continuous panel of woven wire mesh. The exposed face is then lined with topsoil and seededwith grass.
