Fluid flow can deform a porous material if the pressure is large enough, or if the material is soft enough. These poromechanical deformations occur across biophysics and geophysics, from the mechanics of human tissues to the recovery of oil and gas, but they are notoriously difficul to study in a laboratory setting. Here, we achieved this by injecting fluid into a packing of soft particles.
Left: Injection of fluid (arrows) into a packing of soft particles deforms the packing, opening a cavity around the injection port. Bands of shear failure (red patches) lead to wedge-like displacement patterns reminiscent of flower petals (white to blue).
Read the paper and watch some videos: MacMinn et al., PRX 2015.