|
|
|
|
|
|
|
|
|
|
Large Amplitude Oscillatory Shear measurements of fire ant aggregations
Michael Tennenbaum and Alberto Fernandez-Nieves
We have previosly investigated the mechanics of fire ant aggregations using oscillatiory rheology in the linear regime. We are currently working on extending our understanding into the non-linearities of the mechanics. To do this we employ Large Amplitude Oscillatory Shear (LAOS) experiments.
To see how the waveforms change with strain and frequency we can plot the stres curve against the strain curve to get Lissajous curves, figure 2.
We can do this test for a range of strains and frequencies and volume fractions. One volume fraction is shown in figure 3.
So far we can see strain stiffening behavior at high strains and frequencies. We are working on caracterizing this behavior furthur and elucidating how this behavior arrises from the individual ants behavior.
|
Soft Condensed Matter Laboratory, School of Physics, Georgia Institute of Technology
770 State Street NW, Atlanta, GA, 30332-0430, USA
Phone: 404-385-3667 Fax: 404-894-9958
alberto.fernandez [at] physics.gatech.edu