HITACHI CONSTRUCTION MACHINERY

Before construction can start on Vienna’s new central railway station, extensive demolition work must be carried out on the city’s south railway station. Facing strict deadlines and environmental regulations, as well as growing media attention, general contractor Porr Umwelttechnik GmbH and its Hitachi excavators will ensure that the first trains arrive on time in 2012.

One of the largest construction projects in central Europe is currently underway in the Austrian capital. The regeneration project in south-east Vienna covers 109 hectares and will result in a new district of the city, with residential accommodation, office buildings, a school campus and park land. It also includes the replacement of the former Vienna Südbahnhof (south railway station) with a larger Hauptbahnhof (central railway station).

Since the 1950s, Vienna Südbahnhof has been the final stop for many rail journeys from the south and east of the city. A mass of concrete and glass, many Viennese viewed it as an eyesore at worst, or the result of practical post-war planning at best.

The Südbahnhof was built on the site of the Gloggnitzer Bahnhof, which was completed in 1841, then replaced by a bigger and better neo-Renaissance style station in 1874. When the new station opens in 2012, it will therefore be the fourth railway station to exist in this part of the capital.

The Hauptbahnhof will connect two previously separate terminals under one roof, levelling their height difference of approximately four metres. Trains from all directions will be able to stop at Vienna and continue travelling through the city. The Hauptbahnhof will become one of the most important European travel hubs, with faster connections to Austria’s neighbouring countries.

The old station was closed in December 2009 before demolition of the main ticket hall began in January 2010. While the work is being completed, a temporary station is open nearby and a railway line through the job site remains in use. Underground trains also continue to run beneath, and tram lines operate parallel to the perimeter of the job site. Porr is one of the two general contractors responsible for demolition and material processing at the site. According to Martin Taborsky, Porr’s Construction Manager, the job site’s proximity to existing rail lines, underground and tram routes, is just one of many challenges.

“The demolition work must be complete in six months,” he says. “Despite the urgency, the demolition can only be carried out five days a week, from 6am to 10pm, to keep noise disruption to local residents to a minimum. However, 6am is an early start for an inner-city project like this.

“Vibrations are also monitored regularly at different points around the 80,000m² site. We have to make sure we’re not exceeding the limit – so far, we haven’t had any problems.”

After the ticket hall has been demolished, Porr must dismantle two large concrete bunkers beneath it. “It will take eight weeks to remove them: one is 6,400m²; the other is 3,200m²,” continues Martin. “We intend to dig to a depth of seven metres around each bunker and will use a five-tonne hydraulic hammer to demolish them.”

In addition to the demolition work, Porr must also ensure that all materials are separated so they can be reused on site, where possible. “Separation of material is a big part of our contract and recycling is very important,” adds Martin. “Up to 80 per cent of materials will be used for the construction of the new station, and the remainder will be sold and used on other sites.”

A total of 380,000 tonnes of concrete, steel and other materials must be transported by truck to stockpiles at the rear of the site. This amounts to 400 truck loads per day, travelling around the site’s self-contained road network.

Porr has 20 trucks and 20 excavators on the site. Two of its Hitachi demolition machines are being used to dismantle the main ticket hall. The steel from the window frames is removed by a ZX350LC-3 with a 21m high-reach boom and combined shears and cutter attachment. A ZX470LCH-3 fitted with a 27m high-reach boom is helping to remove the concrete in between the window frames.

Both models were supplied by the official Hitachi dealer in Austria, Baumaschinen Handel GmbH. According to Sales Area Representative Gerhard Glock, the demand for larger and more powerful machines is increasing among customers, due to the considerable amount of concrete and steel used in buildings originally constructed in the 1950s and 1960s. “Height is not a problem, but power is an important issue,” says Gerhard.

Several other Hitachi excavators can be seen at the site, including a ZX250LCN-3 with grab attachment, which is processing materials from the old ticket hall. Porr has hired three additional Hitachi excavators from demolition company Prajo. These include a ZX350LC-3 with 23m high-reach and claw attachment, ZX240N-3 with pulveriser attachment and a ZX210LC-3 used for loading materials on to the trucks.

Porr selected Hitachi construction machinery after a comparison of different brands over several years. “The decisive factors were fuel consumption, running costs, and the number of working hours against repair costs and downtime,” explains Martin. “Performance is key for demolition, not cost – we only have six months to do the work, and the costs that can result from not completing work on time far outweigh the cost of a machine, or differences in costs between models. This was the most important factor in the company’s decision to buy Hitachi machines.”

The Vienna Südbahnhof is one of the most high-profile job sites in Austria. Its progress is photographed by members of the general public, has been reported on by local media and even filmed by a national TV station. The presence of Hitachi construction machinery is a huge endorsement for the brand. “It’s like a huge shop window for Hitachi and for Baumaschinen Handel GmbH,” jokes Gerhard.

Demolition in Austria has a comparatively small share of the overall construction market, which makes it even more competitive. “There are probably ten to 12 Hitachi demolition machines in Vienna, and a total of 20 in Austria,” adds Gerhard. “Many machines are standard and configured for demolition, so they are versatile for use on other projects,” he says. “That’s why it’s remarkable to see so many Hitachi machines working on this one demolition site.”