Feature -Have you ever wondered what could have been, if New Orleans and the federal government had been prepared for a devastating Hurricane such as Katrina? How many lives, structures and businesses could have been saved? Where do you put your money to build up a region’s defense against the next natural disaster? These are the questions scientists from the Mid-America Earthquake Center (MAE) are trying to answer in order to prepare local, regional and federal governments for a destructive earthquake that will hit the Midwest sooner or later.
 
Chasing news from the desk sometimes can distract you from what is going on in the real world and while I am personally not the guy who likes waiting at airports to jump on a crowded plane and fly coast-to-coast to visit press events (luckily we have other editors here at TG Daily who like to do that), an opportunity to leave the office for half a day to see something new is a welcome change.

Such an opportunity recently came along when Trish Barker, PR representative for the National Center of Supercomputing Applications (NCSA) at the University of Illinois at Urbana-Champaign, invited me to visit the MAEviz team at the Mid-America Earthquake Center (MAE). MAEviz sounded about as familiar to me as it might to you right now (I had no idea what it was), but some research revealed that these guys are involved in predicting earthquake damage and that indication alone was interesting enough to justify the three hour drive down to the NCSA and learn how advanced earthquake research and damage prediction is these days.

The researchers were nice enough to walk me through their projects over several hours and patiently answer my questions and the more information I absorbed and wrote down, the more I wondered how this fascinating and complex work could be combined into an article. Close to the end of the day, I felt convinced that the prediction of earthquake damage is, in its very basics, very similar to playing SimCity. If you are in your late 20s or somewhere in your 30s and had access to a PC early on, I am sure you are familiar with this title (and if not, check Abandonware sites to download the game or play an online version here): You build a city, strategically place city services, balance a tight budget, come up with a structure of residential, business and industry areas, fine-tune the infrastructure over time in order to build a strong economy and prepare for disasters such as floods, fires or earthquakes (not to mention SimCity’s monsters).

MAEviz could be considered a very sophisticated and scientific version of SimCity. However, here you are not building a virtual city, but you are working with real cities, real streets, real businesses, real resources and also real lives. And it may reveal vulnerabilities of U.S. cities you may not expect, not like and not hear about from your government – for understandable reasons: At the very least, such data may give terrorists an easy map where U.S. cities are most vulnerable.  


Construction and destruction

Much of the earthquake damage prediction is done through computer simulation, but simulation needs real-world data in order to be credible mature over time. The MAE, led by Amr Elnashai, is headquartered at the University of Illinois and is spread out over the University of Michigan, Washington University, University of Memphis, Georgia Tech, Texas A&M, University of Texas at Austin and the University of Puerto Rico, pulls data from a variety of sources, including its own engineering efforts.

The Newmark Structural Engineering Laboratory building of the University of Illinois in Urbana hides a huge construction hall that is actually used to construct or reconstruct actual concrete and steel structures to test their seismic vulnerability. An enormous, three story high concrete/steel wall (six feet of the structure are anchored into the ground) is used as the front end of engineering tests. It holds a movable steel structure weighing “several hundreds of tons” that can put structures such as reconstructed bridge piers under enormous horizontal and vertical stress. While it was unclear just how powerful this apparatus is, I was told that the setup can hit structures with about a million pounds.     
It is hard to comprehend how much force that is, but it is definitely enough to reveal the limits of any concrete structure.

The process in itself is provided by the NCSA as a service to researchers who received the funds to run such a test (typically $50,000 for an average test run that includes construction (of one pier for about $17,000) as well as destruction and will yield several gigabytes of test data). The data set resulting from such a test belongs to a researcher for a time frame of about six months. After that, the Network for Earthquake Engineering Simulation (NEES) will request the data for archival purposes.
 
I was told that the facility also accepts requests from outside parties such as governments or companies. In all sincerity of the matter, walking through the construction hall gives the inexperienced visitor a sense of a huge playground for earthquake researchers – a dream come true for anyone who likes to build elaborate sandcastles and later level them to the ground. NCSA representatives said that there is currently a testing backlog of a few months for the facility. Once a test is approved and scheduled, it takes about four weeks to set up a test.

Simulated impact on a pier

There is an enormous complexity behind those tests with numerous variables impacting an actual damage to a structure during an earthquake. Depending on the soil, the angle and the strength an earthquake hits a structure, the outcome may be very different. The MAE team says that there simply isn’t enough data to reliably simulate an impact of an earthquake on a bridge through a computer, which is why there are actual physical tests. However, researchers do simulate bridge spans since they do not “travel” during an earthquake. If a bridge collapses during earthquake, it will not be because of the span, but because of the piers, I was told.

There are many fascinating tests going on and I have to admit that I was surprised to learn about the dangers of a possible earthquake in the Midwest, which is apparently just a matter of time and could be much more devastating than an earthquake caused by the St. Andreas fault. The New Madrid fault was the origin in an 1812 quake, which was felt all the way to Washington DC. It is expected that the fault will cause an earthquake very 200 to 300 years, which means that the risk for the Midwest is already substantial. It is worrisome worrying is the fact that there have been very few earthquake preparations in the Midwest and the soft soil along the Mississippi river, whose water has penetrated the ground of nearby to a depth of about 1000 m (3000 ft), provides a perfect scenario for a very destructive quake.  According to the MAE scientists, a strong New Madrid quake could travel far, causing skyscrapers to shake and causing windows to fall out of buildings as far as Chicago.

Simulated impact on a wall

Closer areas, such as Memphis or St. Louis could be affected in a much more serious way, we heard, and facing what is now commonly described as the Katrina of earthquakes. Most of us are very aware of Katrina, which has become a synonym for natural disasters that should be taken serious. At the very least, Katrina has woken up people and government agencies that there are real natural threats we should be prepared for.

Apparently, the danger of such a quake is known among scientist and even government agencies, but what exactly is done about? Well, Memphis simply should not have been built where it has been built in the first place, we were told. But correcting that mistake and leveling the city to the ground, or relocating it a few hundred miles away, is not a realistic option. So scientists are trying to find ways to limit the potential impact of an earthquake through simulation: Governments can use the findings and data to reorganize a city structure and limit damage to structures and the economy as well as loss of life.

Read on the next page: Simulating the worst case scenario