Grouting Leonardo’s canal

The extension of the Milan Metro Red Line, currently being constructed by Grandi Lavori Fincosit, runs through notoriously boggy ground on its way from Famagosta Station to Abbiategrasso square. En route it runs under a canal, and so has to be carefully prepared to prevent leakage and possible tunnel collapse; and especially so when the canal in question has been designed by Leonardo da Vinci (to supply materials for Milan’s cathedral) and is a national treasure.

Contractor ELSE is responsible for consolidation jet grouting along the route, which is effected by drilling holes up to 34 m deep and filling them with concrete under pressure. During the most critical part of the work, the canal above the tunnel is to be dammed to prevent any possible flooding. Electricity and air pressure for the reinforcing work is being supplied by Atlas Copco, which has provided two QAS108 100 kVA generating sets and a XAHS365 portable compressor. The gensets are supplying general site power as well as electricity for two concrete batching plants and have been found to be 20 per cent cheaper than mains power. The project is due for completion in January 2003, by which time 2.8 million cubic metre of concrete will have been put in place.