It took just a matter of seconds to flatten L’Aquila in Central Italy. The earthquake, magnitude 5.8, killed 308 people there and in the surrounding region. It was early morning, April 6. 50,000 people were made homeless overnight.
Earthquake survivor Federico Porfirio said: “I still remember that night. My bed moved from one place to the other. All my books fell. I could hear a terryfing sound from outside; debris was crashing down in the street. I will never forget it.” The town centre is off-limits to eveyone except the police, firefighters and civil engineers. They are trying to assess how much of the region’s historic architecture can be saved. And they are putting their faith in a modern application of an ancient art. They hope technical textiles made from carbon-fibre and glass-fibre will be able to stabilise shattered structures. Civil engineer Giulio Morandini said: “To protect this building more, first we’ll have to protect these pillars. We’ll have to clean the surface, leaving just the concrete, and fix our carbon-fibre textiles, principally at the base of the pillar. Depending on the kind of protection the engineer wants to achieve, you could use carbon fibre or glass-fibre. Both products are really flexible and thin, and can easily adapt themselves to whatever geometry of the structural element you want to protect”. 500 kilometres north of the quake’s epicentre, in the countryside near Venice, engineers are weaving a tangled web of the 21st century. The European research project Polytect is working on the multifunctional textiles of the future. These materials are intended to protect structures during – or after – earthquakes, landslides and other natural disasters. With sensors built-in, they will be able to see, hear and smell trouble before it happens. Structural engineer for D’Appolonia SpA, Thomas B.Messervey said: “The idea is simply to make architectural structures more like the human body, and to build a skin for those structures. So by combining the information that we can obtain from sensors, we can build a relationship with the architectural structure overtime. And we can ideally conduct what we call ‘;structural health modelling’ which hopes to answer four questions: Is the damage present? Where is that damage on the structure? How severe is that damage? And finally what does this damage mean? What is the life of the structure after this damage has occurred?” And they are already well advanced with some prototypes. Messervey went on: “There is a product for a masonry structure. The glass fibres go in many different directions, because the stresses and the loads in the architectural structure go also in many different directions. And inside we have sensors, fibre-optic cables in this case, that we can send light through to assess the health and the state of the structure. For geotechnical products, to protect against landslides, we will put these textiles underground in the earth. We can use filter-type products or we can use a grid-like material to both stregthen the soil or to filter water, and still be able to pass light and information throughout our sensors to interrogate whether or not the soil is moving. “Other interesting applications are 3-D rope-like textiles. Inside they have fibre-optic cables that we can make sensitive to chemicals. If we use these in a landfill application, we can detect the presence of chemicals or the temperature of that landfill.” The main technological challenge is to find a quick and efficient way of weaving the sensors into the fabric. Donato Zangani, Polytect’s Project Coordinator said: “We had to develop sophisticated sensors and had to understand what is happening as we went along. Inside the architecture of a building, for example, we have to monitor how much it has deformed, its temperature, humidity, stiffness, or the presence of chemicals. And at the same time, we had to develop techniques to properly knit those sensors into the structure. Another major challenge is to be able to develop laboratory tests to measure and read what those sensors are telling us.” Some of the lab tests are done at Chemnitz in Germany. One experiment is called the “mushroom test”. Samples of polypropylene or glass fibres are deformed to the limit by a large probe that looks like a mushroom. Frank Weigand, an engineer at SFTI explained: “These materials are, in theory, equipped with active sensors which monitor structures under load. So, then we can work out what forces they have already been subjected to. The sensor detects a potential failure of the filters or the mesh. The idea is to protect the sensor from breaking under a limited load, but to allow it to detect a possible failure ahead.” It is a useful way for scientists to learn about how these high-tech textiles deform, how they respond to fatigue, and how much punishment they can take before they reach breaking-point. The machines can weave materials with sensors built-in at speeds of up to 220 meters per hour. And the technical requirements are demanding. Patent Supervisor at SFTI Petra Franitza said: “If I’m doing fashion for the normal clothing industry, there are autumn, winter, spring and summer collections, and I have to react quickly to changing trends. But with technical textiles, I have an entire machine behind me that needs to perform many different functions. “I have to meet certain technical demands that go way beyond fashion.Because here, it’s all about saving lives. Above all, in anti-earthquake construction, it’s not fashion phenomenon, but we want to make homes safer so that houses don’t completely collapse.” The researchers hope their work will be able to allay the fears of those who survive earthquakes like L’Aquila. One of them is Venusia Alonzo. “I still don’t want to go back home,” she explained, “even if they’d let me. I don’t feel safe at home. It’s not been long since the earthquake. After other earthquakes elsewhere in Italy, authorities sometimes gave the authorisation to go back home and then another, bigger earthquake struck. I don’t want to be afraid. I prefer to sleep in this camp”. High-tech textiles are playing an increasing role in protecting property and lives, by becoming an integral part of the fabric of society.
Website : http://www.polytect.net/"