To improve forecasting earthquakes, NJIT mathematician studies grains

December 22, 2008

A new and better way to predict earthquakes and avalanches may soon be available to forecasters thanks to mathematical research underway at NJIT. Using mathematical modeling, researchers are investigating how forces and pressures propagate through granular materials.

"Computational Homology, Jamming and Force Chains in Dense Granular Flows," a four-year, $378,603 National Science Foundation grant has been awarded to Louis Kondic, associate professor of mathematical sciences at NJIT. Kondic will study how the physical properties of granular materials, like sand or salt, can lead to jamming, large force fluctuations and ultimately how they can pressure a building to topple. Both earthquakes and avalanches involve similar materials and reactions.

"The mystery is to learn how forces and pressure propagate or move through grains," said Kondic. "We know the answer for liquids, but for granular materials, we do not. As a result, it is difficult to build efficient devices for dealing with them. Silos can collapse due to non-uniform pressures on their walls. Salt, sand or coal often jams when flowing out of hoppers. But why they behave like this remains unknown."

2006, Kondic was the co-author of "On Velocity Profiles and Stresses in Sheared and Vibrated Granular Systems Under Variable Gravity" which appeared in Physics of Fluids. Other articles by him investigating similar research have appeared in Applied Mathematics and Mechanics (2008), SIAM News (2007) and Physics Review E (2005). To view Louis Kondic's bio, please visit this link

(ATTENTION EDITORS: To receive copies of the articles or to interview Kondic, call Sheryl Weinstein, 973-596-3436.)

The current project centers on so-called force chains, which are crucial for understanding granular systems. The attached figure shows computer simulations of heterogeneous, ramified structures (colored yellow). "Similar forces do not propagate uniformly, but instead form chain-like structures," said Kondic. "We will propose new mathematical methods for quantifying these structures. The algorithms will account for the geometrical properties of the forces. Such a generalized model that describes the properties of these features does not exist."

According to Kondic, the research applies to earthquakes and avalanches because when tectonic plates move, they can cause an earthquake. Where the points of these plates meet, the material will typically be in a granular form. Researchers now believe that a better understanding of the forces that exist in this granular state can lead to new methods for predicting when and where earthquakes and/or avalanches will occur.

This project will employ a highly interdisciplinary approach that integrates new geometrical techniques, modeling, and experiments. It will address fundamental questions concerning the physical properties of granular media and other jammed materials such as glasses, foams, and colloids.

Although the existence of force chains has been known for decades, a quantitative understanding of their role in physical processes has proved to be elusive because previous studies have been unable to devise an unbiased and general definition for them. Precise identification and characterization of force chains and the response of jammed materials to applied forces will likely have a transformative impact in many arenas.

The NJIT study is part of a larger NSF project involving Robert P. Behringer, professor of physics, Duke University; Konstantin Mischaikow, professor, department of mathematics, Rutgers University-New Brunswick; Corey O'Hern, associate professor, departments of mechanical engineering and physics, Yale University.
NJIT, New Jersey's science and technology university, at the edge in knowledge, enrolls more than 8,000 students in bachelor's, master's and doctoral degrees in 92 degree programs offered by six colleges: Newark College of Engineering, New Jersey School of Architecture, College of Science and Liberal Arts, School of Management, Albert Dorman Honors College and College of Computing Sciences. NJIT is renowned for expertise in architecture, applied mathematics, wireless communications and networking, solar physics, advanced engineered particulate materials, nanotechnology, neural engineering and e-learning. In 2006, Princeton Review named NJIT among the nation's top 25 campuses for technology and top 150 for best value. U.S. News & World Report's 2007 Annual Guide to America's Best Colleges ranked NJIT in the top tier of national research universities.

New Jersey Institute of Technology

Related Earthquakes Articles from Brightsurf:

AI detects hidden earthquakes
Tiny movements in Earth's outermost layer may provide a Rosetta Stone for deciphering the physics and warning signs of big quakes.

Undersea earthquakes shake up climate science
Sound generated by seismic events on the seabed can be used to determine the temperature of Earth's warming oceans.

New discovery could highlight areas where earthquakes are less likely to occur
Scientists from Cardiff University have discovered specific conditions that occur along the ocean floor where two tectonic plates are more likely to slowly creep past one another as opposed to drastically slipping and creating catastrophic earthquakes.

Does accelerated subduction precede great earthquakes?
A strange reversal of ground motion preceded two of the largest earthquakes in history.

Scientists get first look at cause of 'slow motion' earthquakes
An international team of scientists has for the first time identified the conditions deep below the Earth's surface that lead to the triggering of so-called 'slow motion' earthquakes.

Separations between earthquakes reveal clear patterns
So far, few studies have explored how the similarity between inter-earthquake times and distances is related to their separation from initial events.

How earthquakes deform gravity
Researchers at the German Research Centre for Geosciences GFZ in Potsdam have developed an algorithm that for the first time can describe a gravitational signal caused by earthquakes with high accuracy.

Bridge protection in catastrophic earthquakes
Bridges are the most vulnerable parts of a transport network when earthquakes occur, obstructing emergency response, search and rescue missions and aid delivery, increasing potential fatalities.

Earthquakes, chickens, and bugs, oh my!
Computer scientists at the University of California, Riverside have developed two algorithms that will improve earthquake monitoring and help farmers protect their crops from dangerous insects, or monitor the health of chickens and other animals.

Can a UNICORN outrun earthquakes?
A University of Tokyo Team transformed its UNICORN computing code into an AI-like algorithm to more quickly simulate tectonic plate deformation due to a phenomenon called a ''fault slip,'' a sudden shift that occurs at the plate boundary.

Read More: Earthquakes News and Earthquakes Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to