Elastic materials

Our work covers

• Elastic waves, including vibration and ultrasonics
• Constitutive theory of nonlinear elastic materials, which is mostly applied in soft tissue biomechanics
• Coupling soft-tissue stress with instability patterns and elastic waves.

Linear elastic waves

Linear elastic waves cover ultrasonics, and are used to make measurements and assess materials. Work in this includes methods to measure stress through changes in wave-speed with applications in steel and hard solids, medical ultrasound, and measuring extremely thin membranes.

Another theme is use elastic waves in more complex geometries to measure shape changes as well as sources and stress. Our first paper on the theme …

Initially stressed solids

The driving question is how to mathematically describe the mechanical response of residually stressed solids? Our main contribution has been revealing a new symmetry, a result from conservation of energy, that restricts the possible mechanical responses. The image at the top of this page shows arrows which indicate the direction of the residual stress of a thick tube. The material is in equilibrium.

instability patterns

Most biological materials (and industrial) are reinforced with stiff fibres or are under tension. I figure out how these mechanisms influence elastic surface waves and the formation of surface wrinkles. The main reasons to do this are

• Will give us greater control over surface waves or forming textured surfaces (using surface wrinkles).
• Use these surface waves and surface wrinkles to measure biological materials.