research
Contact stiffness of rough surfaces
Contact stiffness of multiscale surfaces by truncation analysis
In this concise piece of work, an effective method is shown to gain new understandings into the role of surface structure in the field of contact mechanics. In particular, normal contact stiffness is correlated to parameters of surfaces' fractal dimension and amplitude.
3D printing of simulated geomaterials
https://doi.org/10.1680/jgeot.15.P.034
This work, dating back to 2015 demonstrates the simulation of grain morphologies for subsequent fabrication of surrogate geomaterials
Abstract
Curvature suppresses tensile wrinkles
Transverse wrinkles usually occur in a uniaxially tensile elastic membrane and will be smoothed upon excess stretching. This instability-restabilization response (isola-center bifurcation) can originate from the nonlinear competition between stretching energy and bending energy. Here, we find a crucial factor, the curvature, which can control effectively and precisely the wrinkling and smoothing regimes. When the sheet is bent, the regime of wrinkling amplitude versus membrane elongation is narrowed, with local wrinkling instability coupled with global bending.
electroadhesion of rough surfaces, with application to touch screen technology
Just submitted a paper on electroadhesion of rough surfaces, greatly simplifying the recent theory of the great Bo Persson , with hot application to touch screens : see here.
Comments welcome.
The remarkable mechanical properties of crumpled materials
Mechanics of crumpled materials
Crumpled materials exhibit unusual and as yet unexpained mechanical properties. Through the surprisingly complex morphologies of facets and ridges formed in the crumpling of paper into a ball or densser materials, very high strength to weight ratios can emerge.
Fracture mechanics of porous materials
Fracture mechanics of porous materials
https://doi.org/10.1016/j.engfracmech.2015.10.004
The effects of pore geometry on fracture mechanics is studied by considering notches of various types with a uniform crack growth. This work, published in Engineering Fracture mechanics, sheds light on the role of stress concentrators in the toughness of porous materials.