In the field of elastography [l], biological tissues are typically assumed to be purely linear elastic solids. However, several tissues including been known to be poroelastic. We recently developed brain, cartilage and edematous soft tissues, have long a method to estimate the local Poisson's ratio in linear elastic solids [2]. In the current study we use the same method to measure the time-dep...

We develop a method of poroelastic relaxation indentation (PRI) to characterize thin layers of gels. The solution to the time-dependent boundary-value problem is obtained in a remarkably simple form, so that the force-relaxation curve obtained by indenting a gel readily determines all the poroelastic constants of the gel—the shear modulus, Poisson’s ratio, and the effective diffusivity. The met...

Introduction: Hydrocephalus (HC) is a disease characterized by obstruction of cerebrospinal fluid (CSF) flow in either the lateral ventricles (noncommunicating) or subarachnoid space (communicating), resulting in an increase in ventricular size and a subsequent increase in intracranial pressure (ICP). Currently, magnetic resonance imaging or computed tomography assist in diagnosis, but these im...

The most commonly used prediction techniques to study the steady state behaviour of coupled acousticporoelastic problems are based on the Finite Element Method. However, due to the large computational load when frequency increases, these methods are restricted to low frequency problems. Recently, a Wave Based Method was developed to tackle this type of problems in a more efficient way. The meth...

In this paper we investigate the limit behavior of the solution to quasi-static Biot’s equations in thin poroelastic flexural shells as the thickness of the shell tends to zero and extend the results obtained for the poroelastic plate by Marciniak-Czochra and Mikelić in [16]. We choose Terzaghi’s time corresponding to the shell thickness and obtain the strong convergence of the three-dimensiona...

Poroelastic materials are often used as sound and vibration reduction measures in many engineering applications. Their dynamic behaviour is accurately described by the theory of Biot. The Finite Element Method is most commonly used to simulate such materials, however, is only applicable for low-frequency applications due to the associated computational cost. This extended abstract describes the...

Current diagnosis of bone loss and osteoporosis is based on the measurement of the Bone Mineral Density (BMD) or the apparent mass density. Unfortunately, in most clinical ultrasound densitometers: 1) measurements are often performed in a single anatomical direction, 2) only the first wave arriving to the ultrasound probe is characterized, and 3) the analysis of bone status is based on empirica...

In this work, we present the Poroelastic Relaxation Indentation (PRI) testing approach for quantifying the mechanical and transport properties of thin layers of poly(ethylene glycol) hydrogels with thicknesses on the order of 200 mm. Specifically, PRI characterizes poroelastic relaxation in hydrogels by indenting the material at fixed depth and measuring the contact area-dependent load relaxati...

Viscoelasticity and poroelasticity commonly coexist as time-dependent behaviors in polymer gels. Engineering applications often require knowledge of both behaviors separated; however, few methods exist to decouple viscoelastic and poroelastic properties of gels. We propose a method capable of separating viscoelasticity and poroelasticity of gels in various mechanical tests. The viscoelastic cha...

A general analysis of poroelasticity for vertical transverse isotropy (VTI) shows that four eigenvectors are pure shear modes with no coupling to the pore-fluid mechanics. The remaining two eigenvectors are linear combinations of pure compression and uniaxial shear, both of which are coupled to the fluid mechanics. After reducing the problem to a 2 × 2 system, the analysis shows in a relatively...