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DOWNER IN BLACK & WHITE / 11 building two extra custom-drilling rigs using motors flown in especially from the USA, all within two weeks. The project team put forward other ideas to save time. The first was to use road milling machines instead of jackhammers to break up the floor of the tunnels. The second involved the steel rods drilled into the tunnel walls. There are 1,800 of them, and each was to have a square retaining plate attached to it, recessed into the wall by hand. However by using round retaining plates instead, the recesses could be bored using drilling rigs, cutting total installation time by days. “I had never seen it done this way before, but it seemed logical,” says Harrison. “The idea came when some of the guys were brainstorming on how they could do the job faster. They came up with a neat, quick and very effective solution. Although, then we had a “rush-on” to secure the round plates from our supplier – they were made to order,” laughs Harrison. “To mill the rock on the bottom of the tunnels we used milling machines that are usually used to remove asphalt on motorways,” explains Harrison. “We did a fair amount of testing beforehand to make sure that they could be used for this purpose. We would normally use jackhammers and rock saws (large rotating blades) for this kind of work. Adapting equipment in this way, we completed this part of the work in eight days instead of 15,” he says. The project team worked 45,000 hours plus without a single lost-time incident. Harrison attributes this to the strong safety culture led by Downer and Kiwi Rail, which was taken on board by the whole site team, including staff from the 15 different sub-contractors. Downer also had its own health and safety person on site throughout the entire project. “It was a tribute to the whole team that they understood the risks and respected the measures we had in place to manage them,” says Harrison. “With the job delivered on time,” says Headifen, “the cherry on top was winning the 2012 Biennial Railway Project award from the Railway Technical Society of Australia – an award presented to him at a gala dinner in Brisbane on 12 September 2012. The excavation has increased the height of the tunnels’ roofs by more than half a metre to 5.5m and trains can now travel at 70km per hour instead of 40km per hour, and carry larger loads. “The project presented some massive challenges along the way, and the Downer team never faltered,” says Headifen. “I’m not denying that there were some really hard parts during the project and I felt we were on the edge some days. But the guys at Downer and the sub-contractors pulled it off.” Headifen, who won the Chartered Institute of Logistics and Transport in New Zealand Young Achiever of the Year on the back of this rail project, believes that people want the ability to move bigger, heavier loads by rail. “Rail might not be able to go to the corner dairy, but we can carry hundreds of tonnes in one go.” “There are many more tunnels throughout New Zealand that need upgrading, he says, with a twinkle in his eye, “and rolling stock is getting bigger.” DOWNER / IN BLACK & WHITE / 55


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