'Seismic fabric' could earthquake-proof vulnerable structures
07 January 2013
Researchers have developed a new 'seismic fabric' which can be retrofitted to vulnerable structures, gaining occupants escape time in the event of an earthquake.
Walls are 'papered' with sheets of seismic fabric and then plastered over (photo: M. Urban/KIT)
The product, developed at Karlsruhe Institute of Technology (KIT), extends the time for saving lives by reinforcing walls and preventing debris in the event of an earthquake. A building materials manufacturer has now commercialised the development of a reinforcing earthquake fabric.
For several years, Lothar Stempniewski and Moritz Urban have investigated possibilities of securing and reinforcing the earthquake-prone walls of older buildings. They developed a glass fibre reinforced plastic fabric with four fibre directions. Using an appropriate plaster, this special seismic fabric is applied to vulnerable building elevations to delay or avoid altogether the debris that results following an earthquake.
Under the brand name 'Sisma Calce', the Italian building material manufacturer Röfix, a subsidiary of the German Fixit Group, has now included the seismic fabric and special plaster in its product range.
“Particularly in the case of short and moderate earthquakes, not much more additional tensile strength is needed to avoid the collapse of a building,” explains Urban.
The high stiffness and tensile strength of the glass fibres in the quasi plaster-integrated fabric allow walls to dissipate stresses during earthquakes and avoid the propagation of cracks. Should the fibres rupture during a strong earthquake, the elastic polypropylene fibres will hold broken wall segments together, giving occupants more time to escape the building. Under advantageous conditions, the walls may even stay intact and houses could be repaired after the earthquake.
Co-operating companies Bayer MaterialScience AG, MAPEI SpA and Dr Günther Kast GmbH & Co KG, are currently preparing an adhesive seismic fabric for indoor use. Both brick/stone and concrete walled buildings are being considered. In the case of concrete, higher forces must be absorbed, and the team is currently testing new materials with carbon fibre reinforcement for these particular structures.