Teaching atomistic approach in mechanics labs could help transform civil engineering practices
An educational experiment in a January short course at MIT demonstrated that students can learn to apply sophisticated atomistic modeling techniques to traditional materials research in just a few classes -- an advance that could dramatically change the way civil engineers learn to model the mechanical properties of materials.
Markus Buehler, a professor in MIT’s Department of Civil and Environmental Engineering, noted that while scientists often rely on quantum mechanics in their study of materials, engineers tend to use a more traditional continuum approach. But a fracture in a concrete bridge doesn’t begin as a long, jagged scar; it starts off as a vibration at the atomic scale and progresses.
Buehler believes there could be enormous benefit to industry if civil engineering educational practices evolve to make it easier for students to think about the molecular architecture of materials. Utilizing the atomic scale in materials design and analysis could open opportunities for significant improvement in material strength, reliability and sustainability.
Buehler worked with Ivica Ceraj, a software developer in MIT’s Office of Educational Innovation and Technology, to create a simplified way of teaching students how to relate a material’s response on a large scale to its atomic structure using atomistic simulation.
In order to make this complex modeling process accessible, the two employed a web interface called GenePattern, award-winning software developed in 2004 by a team at the Broad Institute of MIT and Harvard to help scientists perform gene expression analysis. Ceraj created an interface between GenePattern and the software code Buehler uses in his own research on materials as disparate as collagen and concrete. The combination provides a simple-to-use, but very accurate tool for modeling the behavior of materials under extreme loading.
Engineering students usually study typical beam-loading problems during their first years in college, but aren’t taught how a material’s response at larger scales relates to its structure and mechanisms at the atomic level. Buehler found that when using the web interface method, students learned the basics of atomistic modeling quickly, then applied the technique to predict the mechanical properties of silicon, copper nanowire, and a structural protein called vimentin that plays a crucial role in stabilizing eukaryotic cells under deformation. Previously, such simulations were difficult to carry out and required students to learn technical details of operating a Linux workstation before they could get to the heart of the numerical method. As a result of the new method, students not only learned the atomistic simulation quickly, some have already adopted it for their own applications.
For additional information, write to OnBalance@mit.edu.
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