Engineers from the Vienna University of Technology have used a new construction method to create a dome made out of inflatable slabs of concrete.
The technique involves a flat slab of concrete hardening on the ground, followed by an air cushion inflating below the plate, which bends the concrete and quickly forms a sustainable shell, according to PDDNet.
The method has been used to build an experimental structure in Vienna.
"It is similar to an orange peel, which is regularly cut and then flattened out on the table," said Prof. Johann Kollegger, engineer at TU Vienna and co-inventor of the technique. "We do it the other way around, starting with a flat surface and then bending it to a shell."
Kollegger developed the construction technique with Benjamin Kromoser, engineer at TU Vienna. The technique was successfully tested on the Aspang Grounds in Vienna.
The engineers poured concrete into a form with several segments that were separated by spaces shaped like wedges. After the concrete hardened and the air cushion inflated, steel cables were used to tighten the segments to make sure they raised together, Discovery News reported.
The wedged-shaped spaces helped the segments fit together perfectly once the dome was raised. The structure was then plastered.
While small cracks appear when the concrete is bent, they do not pose a problem for the dome's stability, PDDNet reported.
"We can see that in old stone arches," Kollegger said. "If the shape is right, each stone holds the others in place and the construction is stable."
The engineers said the technique has the potential to be used to build a variety of structures.
"We decided not just to create a simple, rotationally symmetric shape," Kromoser said. "Our building is a bit drawn-out, it cannot be described in simple geometric terms. We want to show that using our technology, even complex free-form structures can be created."
The researchers were able to build the 9.5-foot dome in about two hours, Discovery News reported.
The Austrian Federal Airways authorized the construction of a deer pass over two high-speed rail tracks in Carinthia after witnessing the results of the technique.
