Example work: technical article for Tunnels Magazine
In with the new: high-tech tunneling through Norway
On site at the new project that’s paving the way for Norwegian construction
Along the majestic scenery of northern Norway, under the feet of the summer’s hikers and in the face of the winter’s harsh conditions, PNC Nordic AS (PNC) are creating a new road that will travel through two mountains and over one lake. It’s the first tunnel project of its kind for PNC in Norway, and they’re working together with Sandvik to take on the task.
A short flight from Bodø in Norway, a 30-seater propeller plane hits Mo I Rana landing strip with a soft bump. It’s a tiny airport fit for the small industrial town, tightly flanked by towering mountains and clear blue fjords. Home of the midnight sun, the area sees hundreds of caravaners and holidaymakers flocking here in the summer, to walk the varied mountain pathways, swim, sail and fish in the surrounding water and enjoy the refreshing atmosphere. The access roads around the area are seemingly endlessly winding, and narrow enough to make any driver nervous as large business lorries clatter past.
It is one such road that PNC are revising – route 17. The existing coastline road is slipping slightly and runs at its narrowest past the Liafjellet – a tall mountain with a steep face. Beautiful as it may be, in winter it’s not uncommon to see avalanches that close off the access road completely, cutting off communities and businesses north of the area. At these times, the only form of transport south is by aircraft and boat, which are often also delayed or cancelled due to poor weather.
At the site Project Manager Norbert Hoerlein runs operations with energetic confidence. Hoerlein has been working in the tunneling industry for 20 years, mostly in Austria and Germany. It’s his and PNC’s first tunnel project in Norway. ‘[The project] is a 5km stretch of road which will travel through two mountains – 1800m through Liatind, plus a 400m long tunnel through Bakliholtan, and then bridging over the Olvikvatnet lake,’ he explains. The road will be a comfortable 8.5m wide – much better for those large lorries – and avoiding the steep mountain face and avalanches that come with it. It’s actually a relatively small project for the PNC group – costing around 330m NOK – but that makes it ideal for the company’s first venture in Norway.
Working with Sandvik
Before coming to Norway, PNC had existing connections with the Sandvik dealer Avesco and Sandvik from previous projects. Since the Norwegian project required a powerful and reliable drill rig, they decided Scandinavia’s own Sandvik would be the perfect partner to take on the challenge. On site they’re making the most of the latest Jumbo and iSure drill technology alongside Sandvik’s rock tools, drill bits and rods, resulting in an economic, precise and fast drill and blast process. ‘The rock scanner means we do not need a surveyor for every single blast… the machine drills good, exact holes fast and it doesn’t break down.’ Hoerlein states, ‘It was a good choice to use Sandvik.’ He even makes note of the great sound system in the Jumbo drill – ‘it is just a great working environment.’
With the new technology Sandvik brings with it a new generation of engineers; ‘these new young operators grew up with Playstations and iPhones, and they have a great interest in the data and researching the new tools.’ These ‘digital natives’ that Hoerlein describes are really making the most of the technology on site. Education and automization are the future of the industry, he says, ‘the data and the engineer’. With them working in tandem, they’re ready for the higher level of safety, documentation and accuracy that clients are coming to require.
The relationship between man and machine is an important one, he says. ‘The machines send out such a large amount of data, but it is worthless if you do not have great technicians, engineers and operators to make sense of it. You can buy all the latest machines and technology, but if you do not use the data, you are just drilling like 30 years ago.’ In previous years, Hoerlein says, highly skilled and experienced engineers have been trapped in their offices printing paper, filling in formulas and taking up their valuable time when they could be devising creative solutions: ‘…with this new technology it can be done in one click. Now the engineer has the time to actually work with the data.’
The site has been trialing the new Sandvik iSure program, and Hoerlein notes that it makes it easier to keep clients informed and happy while also increasing the trust between client and contractor. He believes in a transparent way of working, and this technology helps to make that process simple; ‘You deliver accurate information about the project in a straightforward way and then you can arrive at solutions together.’
In this particular project, Hoerlein mentions that they have never had a problem with the stability of the machine and computer system – it has never crashed or failed during use, adding a level of accurate reliability; ‘It’s an absolutely stable system,’ he says. But that’s not all; in work such as bolting it’s possible to use the iSure system to measure the exact position of the bolts, which in turn can be delivered to the client in 3D imaging, to a very high accuracy. ‘Otherwise, a surveyor has to measure tens of thousands of bolts and guess where the end sits in the mountain.’ He continues, ‘This is one step into the future already.’
Norway: the new landscape
The common rock here is gneiss and mica schist – old, solid rock, perfect for building tunnels. The machines can drill 5m blasts at a time – quite a difference from the 1-2m blasts Hoerlein is used to in Central Europe. ‘This is why the technology is so important here,’ Hoerlein explains, ‘in Austria and Germany, where you can only drill one meter at a time, you can’t go too far wrong with each blast. But here in Norway, if you drill by eye only, you can quickly end up a meter away from your planned track. You need the electronics to make accurate progress.’
Inside, the blasted tunnel is sprayed with concrete containing steel fibers, and uses systematic bolting with 3-4m long steel bolts covered with a plastic rust protection, then grouted and filled with cement to support the tunnel.
The rock may be good, but the Norwegian landscape offers its own challenges. ‘We are used to working in snow and mountains, coming from Austria. But one thing that is interesting, rather than a challenge, is that we’re in a remote area here.’ Hoerlein comments, ‘Sometimes it is hard to get the equipment and spare parts that might be required, in the time required. When you have to import it from the EU via Norwegian customs, it can take two weeks to pass through. Which is where good engineers, experienced workshop crew and good project managers add a lot of value, as well as teaming up with local companies and sub-contractors. This helps both to deal with the problem and build a relationship of trust within Norway’s existing companies.’
Becoming integrated and part of the Norwegian tradition is important to PNC. The company is teaching Norwegian language to employees who are non-native speakers, with one in every two workers a Norwegian – despite having a workforce hailing from seven countries. ‘It’s important to adopt the culture of the country. We bring the experience of tunnel and infrastructure building and problem solving in return.’ Hoerlein comments that PNC hopes to bring slab track rail as well as bridge and tunnel construction in Norway to assist with the country’s need for greater infrastructure. ‘We don’t intend to finish this project and disappear – it’s an investment in the future of the country and the company together.’