A team of researchers led by Guoliang Huang, Ph.D., has designed a flexible “cloaking” material that has the potential to help buildings withstand vibrations, such as those created by seismic waves.
The newly developed material is a multilayered, elastic lattice that can be stretched and formed to any surface and applied as a wrap, according to Huang, the James C. Dowell Professor in the University of Missouri’s Mechanical and Aerospace Engineering Department and the leader of its Structured Materials and Dynamics Lab.
The material accommodates nonsymmetrical stresses introduced by energy waves through numerous “collapse mechanisms,” according to Huang. The lattice members produce torque as they rotate, and this behavior allows the material to flex in response to incoming energy waves or vibrations so that the objects inside remain isolated from the impact of the waves, according to Huang. “Therefore, it is particularly useful for protecting against vibrations that might damage a structure,” he says.
The material’s ability to tolerate and absorb longitudinal and shear stresses, such as those caused by earthquakes, is a first. “For over 20 years, no one had a natural solution for this issue in a solid material,” he explains. “The ultimate purpose of the proposed research is to model, design, and fabricate materials that will fill in this ‘behavioral gap.’”
The next steps will focus on the military applications of this coating, particularly in the fields of communications, sensing, imaging, and structural health monitoring, according to Huang. The Army Research Office provided funding for the basic research for the project.
The material’s characteristics also make it useful for the defense industry, as it can protect aircraft or submarines, for example, from vibrations introduced by machinery.
This article first appeared in the Oct. 2020 issue of Civil Engineering.
