The Metropol Parasols will be the new centerpiece of Plaza de la Encarnación in Seville. As well as being an eye-catching work of art, the mushroom-like structures are also playing host to some pioneering construction techniques, with even the load-bearing structural components consisting of finely-wrought laminated veneer lumber beams.
With mechanical joining methods ruled out for structural reasons, the beams are instead joined together by means of glued-in threaded rods. However, the high temperatures and relentless sunshine of a typical Seville summer could pose a significant challenge to the adhesive, in the worse-case it loses its ability to hold the components together.
The type of adhesive used in Seville is designed to withstand temperatures of up to 60 degrees, so researchers from the Fraunhofer Institute for Wood Research WKI have been working on behalf of the building inspection authorities to determine how close the thermal load is likely to come to this limit. “We ascertained the temperatures that might occur at the site and used simulations to determine the temperature this would trigger within the construction materials,” explains Dirk Kruse, head of department at WKI. “Our results revealed that the temperatures in the adhesive could potentially reach almost 60 degrees, which is obviously too close to the limit for comfort.” Subsequent tests carried out on three specimen components in a climate chamber confirmed their findings, giving rise to a stark choice: either the adhesive would have to be improved, or the building inspection authorities would be forced to bring building work to a halt. Fortunately, there is a method of improving the adhesive's resistance to high temperatures, namely by “tempering” the structural components: “Once the components have been glued in place, they are heated up again,” Kruse continues. “This causes post-curing reactions to occur.” And the result? The adhesive is less likely to take on a liquid form and maintains its stability up to a temperature of 70 degrees. This gives a safety margin over and above the thermal stress that is actually expected to occur, which means that the building work can now be continued as planned and Seville will soon be featuring a brand new landmark.
“These are the kinds of solutions that will help to firmly anchor adhesive technology within the building industry,” Kruse states. While adhesive bonding is widely used in the aircraft industry, the use of adhesion for structural applications in the building industry is still in its infancy. Yet the method opens up a whole new wealth of possibilities for architects.
Dirk Kruse | Fraunhofer Gesellschaft
Magnetic liquids improve energy efficiency of buildings
16.01.2018 | Friedrich-Schiller-Universität Jena
Insulating bricks with microscopic bubbles
16.01.2018 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
19.01.2018 | Materials Sciences
19.01.2018 | Health and Medicine
19.01.2018 | Physics and Astronomy