Abraham Moss Tram Stop | Manchester

This lightweight aggregate was used as fill below the platform surface where the substrate was found to be particulary soft and unstable.  The use of Leca® LWA enabled the platform structures to be constructed from concrete sections and quickly and easily filled with the lightweight aggregate. The Manchester Metrolink began operating in 1992 and is currently undergoing a major expansion. The existing three lines which converge in Manchester City Centre will expand to seven by 2016 taking the current length of 23 miles up to 60 and daily rider volume from 56,000 to 190,000. The number of stops will expand from 37 to nearly 100 by the time the expansion is fully open. The latest at the Abraham Moss Leisure Centre required the use of Leca® LWA.

Lawrence Bush of main contractor Spencer Limited managed the design project for the new tram stop, he said “Our ground condition survey found that a big peat layer, some seven or eight metres below the surface, indicated that piling would be required. The time and cost factors of piling did not fit well with the overall expansion plans of the network. The best alternative was to use Leca® LWA which gave us the fill capability without the weight penalty of traditional fill that would have been unstable on the poor substrate land where the platforms run. I had used Leca® LWA previously and knew the advantages.”were easily filled by bulk delivery of Leca® LWA which was loaded into place and compacted. A stone and tarmac capping completed the platform construction. Each pf the two platforms runs for 38 metres and the formwork was constructed quickly from pre-cast sections and blockwork.  These were easily filled by bulk delivery of Leca® LWA which was loaded into place and compacted.  A stone and tarmac capping completed the platform construction. Leca® LWA is a totally natural product. It is lightweight expanded clay formed by heating and firing natural glacial clay in a rotary kiln at temperatures up to 1150°C. This process transforms the clay into lightweight ceramic granules with a hard ceramic shell and porous core. The material is extremely light with a bulk density of just 300kg per cubic metre. Leca® LWA has excellent insulation properties, is free draining, fire resistant, frost resistant and chemically inert with no hazardous properties. Used as a lightweight aggregate fill in many civil engineering applications Leca® LWA reduces the weight on weak substrates and against retaining structures can reduce the weight loading by 75% over traditional fill. Leca® LWA eliminates expensive settlement delays, is easily handled and quickly installed. It is particularly valuable in stabilising slopes where the ceramic granules interlock together and fix the terrain for safety. Expansion of the Manchester Metrolink system continued and Leca® LWA was used for further platform construction.

• Link to contacts page