New Construction Technique – Building With Balloons

New Construction Technique – Building With Balloons

02nd December 2014

Here at Safety Fabrications we’re always on the lookout for innovative and cool new stuff to do with the construction industry – after all, we pride ourselves on being at the cutting edge of safety equipment fabrication. We recently came across a new technique devised by a team at the Vienna University of Technology to build large concrete shells that can save as much as 50% in construction costs.

The Vienna University of Technology was founded in 1815 as the “Imperial-Royal Polytechnic Institute and its teaching and research is focused on engineering and natural sciences. This is a revolutionary building method that has been likened to peeling and orange and lying its skin flat on a table, but in reverse! The inflatable building technique is known as the pneumatic wedge method and it’s something we’re sure to hear more of in coming years as the co-project leaders, engineers Johann Kollegger and Benjamin Kromoser are confident that shells up to 50 metres in diameter should be achievable.

Concrete domes are notoriously challenging to build – the process requires the use of a wooden structure to support the concrete while it hardens. The building work is expensive and time consuming and is usually avoided where possible.

The technique involves pouring a flat concrete slab which hardens on the ground on top of an air cushion which is then inflated to bend the concrete into a sustainable shell. The slab consists of several segments with wedge spaced spaces in between. According to Professor Johann Kollegger of the Vienna University of Technology, it’s absolutely essential to get the geometry accurate for a perfect fit when the structure is inflated and shaped.

The inflatable cushion is actually two plastic sheets that have been welded together to provide a former to shape the shell. As the air cushion is inflated, a steel cable is tightened around the hardened segments of concrete, helping to push it together from the outside and raise the centre. The concrete segments are connected with metal beams to make sure that they move together in perfect synchronicity.

A successful experiment has been carried out using the pneumatic wedge technique on the Aspang Grounds in Vienna to make a 9.5 foot dome in two hours. The Austrian Federal Airways has authorised the construction of a deer pass across high speed rail tracks using this cool new building method. Kromoser predicts that this technology can be used in future to build a range of complex structures, adding flexibility to the cost effectiveness of the process.

We’ll be keeping a close eye on this new construction process in the coming months and we’ll let you know of any further developments in this story. What do you think of this cool new technology – and what sort of effect do you think this will have on the construction industry?