During an earthquake, regular walls get shaken much like humans do. The side-to-side strain causes the masonry to crumble. This year, German materials scientists are producing seismic wallpaper that can hold a wall together.
Karlsruhe Institute of Technology's Institute of Solid Construction and Construction Material Technology has been simulating quake conditions to find better ways to shore up walls since the 1990s. Early attempts involved bonding thin carbon fiber slats to masonry, but that only made the crumbling worse.
Several years ago, they came up with another approach, one in which the surface of a whole wall could be reinforced using special wallpaper. In 2010, the institute's director, Lothar Stempniewski, and his colleagues began perfecting the material.
They used stiff, high-strength glass fibers woven together to form a strong, elastic covering. The fibers run in four directions to distribute energy evenly when the walls are shaking, according to an article by Brigitte Osterath in Deutsche Welle.
This special spun-glass covering alone isn't enough, though. Standard wallpaper glue can't hold up to an earthquake, so the KIT group collaborated with the polymer makers in the materials science division of the chemical company Bayer. They made a flexible, soft adhesive from water and a large amount of polyurethane beads.
Once the adhesive penetrates grooves in the masonry, the water evaporates to anchor the substance in the wall. Similarly, when the wallpaper goes on, it gets completely surrounded by the beads. Together the whole setup won't tear during an earthquake.
To find out just how well it works, the seismic fabric was tested on a replica house in an earthquake simulator.
"Because of the earthquake wallpaper, we were unable to make the building collapse," KIT researcher Mortiz Urban told Deutsche Welle. In a recent press video, Bayer indicated that the wallpaper will start going into commercial production this year through partner companies. It's expected to cost more than regular wallpaper, but the drastic difference for people living in earthquake-prone areas should be well worth the price.
Photo: The earthquake wallpaper is fixed to walls with a special adhesive. Credit: Bayer Material Science.