18 July 2012
Engineers at the Escuela Técnica Superior de Arquitectura de Madrid at the the Universidad Politécnica de Madrid recently announced that they have developed an impressive new method for constructing earthquake-resistant buildings.
Extensive engineering research and development has been targeted toward creating more resilient buildings, but the big achievement of the UPM engineers is that they managed to create a design that could be constructed at low-cost with readily available materials.
A real danger
People living along the West Coast of the U.S. are familiar enough with earthquakes, suffering through the occasional lesser temblor and the rare serious disasters. Even some Americans along the East Coast have gotten their own introductions to seismic activity, with notable earthquakes in Virginia and Eastern Canada that could be felt along much of the eastern seaboard.
But many Americans fail to understand the true scope of the danger posed by earthquakes. From 2000 through mid-July of 2012, the U.S. Geological Survey reports that the country suffered more than 47,800 earthquakes, including 784 temblors of at least 5.0 magnitude. In that time, the agency reports two deaths in the U.S. directly attributable to earthquakes.
By comparison, the USGS reports that the number of 5.0 magnitude earthquakes worldwide reached 2,349 in 2010 alone. In that year, the agency reports the estimated death toll topped 320,000 individuals. While 2010, with a high number of rarer 7.0 to 7.9 magnitude earthquakes, was a particularly deadly year, the USGS reports the lowest estimated death toll in the past two decades was 231 in 2010, with most years ranging in the tens of thousands.
Shaking the developing world
One of the primary reasons for the huge disparity between the U.S. and global death tolls, aside from sheer scale, is that the U.S. has strict standards for building construction and the wealth to afford sturdier homes.
In much of the developing world, where thousands upon thousands can be crammed into crowded slums made of whatever cheap materials are readily available, buildings readily collapse when struck by strong earthquakes. In particular, the researchers at UPM examined constructs of adobe, concrete blocks and hollow brick, finding that all three materials on their own provided little stability.
Framing the problem
What the new engineering research discovered, however, is that these very same materials that were deemed unsuitable on their own could actually be used to create sturdy, reliable buildings when incorporated into an independent framework.
Led by UPM’s Belén Orta, Rosa Bustamente and José María Adell, the researchers created a series of prefabricated steel trusses, which could be easily assembled into a simple building structure. These frames would provide enough stiffness to stand firm against an earthquake, particularly when filled in with materials like adobe and concrete, but also offer enough flexibility to sway along with the vibrations from the quake.
Known as Integral Masonry Systems, this system seeks to provide low-cost options for poorer communities in the developing world without necessarily forcing people or countries to bring in large quantities of new materials. The frames could even be filled with debris and mud, which are often readily available in areas looking to rebuild after a disaster.
Perhaps just as importantly, this design actually proves effective after sustaining damage, simply by repairing cracks in the stone or concrete walls.
The system has been tested twice now at half-scale, and once at full-scale, and could soon begin development for actual production in the coming years.