It is known that design of elastic cloaks is much more challenging than that of acoustic cloaks, cloaks of electromagnetic waves or scalar problems of antiplane shear. In this paper, we address fully the fourth-order problem and develop a model of a broadband invisibility cloak for channelling flexural waves in thin plates around finite inclusions. We also discuss an option to employ efficientl...

The monitoring of both linear and nonlinear elastic properties of a high performance concrete during curing is presented by application of compressional and shear waves. To follow the linear elastic behavior, both compressional and shear waves are used in wide band pulse echo mode. Through the value of the complex reflection coefficient between the cell material (Lucite) and the concrete within...

We propose an elastic scalar imaging condition that corrects for the polarity change; however, this imaging condition requires additional prior information which may not be known accurately, or may suffer from interference of waves propagating from opposite sides of a reflector. Using incorrect Pand S-mode velocities causes reflectors in migrated PP, PS, and SP images to be shifted from their t...

A one-dimensional pure stress initial boundary value problem of linear elastodynamics for amicroperiodic layered semi-space in which amicrostructural length is taken into account is revisited. Also, the plane stress harmonic waves propagating in a microperiodic layered infinite elastic space are discussed. It is shown that (i) for a particular system of the length and time units the transient s...

Elastic waves are scattered by an elastic inclusion. The interface between the inclusion and the surrounding material is imperfect: the discontinuity in the displacement (traction) vector across the interface is taken to be proportional to the average of the traction (displacement) vectors on the two sides of the interface. Uniqueness theorems are obtained, and boundary integral equations over ...

The inverse problem under consideration is to reconstruct the shape information of obstacles or inclusions embedded in the (inhomogeneous) background medium from boundary measurements of propagating waves. This article is a survey of enclosure-type methods implementing exponential complex geometrical optics waves as boundary illumination. The equations for acoustic waves, electromagnetic waves ...

The theory of creeping waves is developed by applying the Sommerfeld-Watson transformation on the normal-mode solution for acoustic scattering from an infinite elastic cylinder. Two types of radiating, circumferential waves emerge: (1) highly attenuated “Franz-type” waves with subsonic speeds, and (2) supersonic “Rayleigh-type” waves which are only slightly attenuated. The experimental study of...

The paper is devoted to analysis of different models that describe waves in fluid-filled and gas-filled elastic tubes and development of methods of calculation and numerical analysis of solutions with solitary waves and kinks for these models. Membrane model and plate model are used for tube. Two types of solitary waves are found. One-parametric families are stable and may be used as shock stru...

The generalized dynamical theory of thermo-elasticity proposed by Green and Lindsay is applied to study the propagation of harmonically time-dependent thermo-viscoelastic plane waves of assigned frequency in an infinite visco-elastic solid of Kelvin-Voigt type, when the entire medium rotates with a uniform angular velocity. A more general dispersion equation is deduced to determine the effects ...

The interface between two wedges can be treated as a displacement discontinuity characterized by elastic stiffnesses. By representing the boundary between the two quarter-spaces as a displacement discontinuity, coupled wedge waves were determined theoretically to be dispersive and to depend on the specific stiffness of the non-welded contact between the two wedges. Laboratory experiments on iso...