Effect of hydration on the frequency-dependent viscoelastic properties of articular cartilage

Abstract Viscoelastic materials are widely used for vibroacoustic solutions due to their ability to mitigate vibration and sound. Wave propagation methods are based on the measurement of the waveform pattern of a transitory pulse in one-dimensional structures. The time evolution of the pattern can be used to deduce the material elasticity and damping characteristics. The most popular propagation methods, namely Hopkinson bar methods, assume no dispersion, i.e. the complex elasticity modulus is not frequency-dependent. This is not significant for resilient materials such as elastomers. More recent approaches have been developed to measure frequency-dependent properties from a pulse propagating in a slender bar. We showed in previous works how to adapt these techniques for shorter samples of materials, representing a real advance, as extrusion is a cumbersome process for many materials. The main concept was to reconstruct the time history of the wave propagating in a composite structure composed of a long incident bar made of a known material and extended by a shorter sample bar. Then the viscoelastic properties of the sample material were determined in the frequency domain within an inverse method held in the time domain. In industry, most isolation solutions using mounts or bushings must support structural weights. This is why it is particularly interesting to know the viscoelastic properties of the material in stressed state. Here, we show how to overcome this challenging issue. The theoretical framework of the computational approach is detailed and the method is experimentally verified.

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Effect of the anisotropic permeability in the frequency dependent properties of the superficial layer of articular cartilage

Computer Methods in Biomechanics & Biomedical Engineering ◽

10.1080/10255842.2018.1504214 ◽

2018 ◽

Vol 21 (11) ◽

pp. 635-644 ◽

Cited By ~ 1

Author(s):

D. Gastaldi ◽

M. Taffetani ◽

R. Raiteri ◽

P. Vena

Keyword(s):

Articular Cartilage ◽

Superficial Layer ◽

Anisotropic Permeability ◽

Frequency Dependent

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Dynamic blocked transfer stiffness method of characterizing the magnetic field and frequency dependent dynamic viscoelastic properties of MRE

Korea-Australia Rheology Journal ◽

10.1007/s13367-016-0031-6 ◽

2016 ◽

Vol 28 (4) ◽

pp. 301-313 ◽

Cited By ~ 11

Author(s):

Umanath R Poojary ◽

Sriharsha Hegde ◽

K.V. Gangadharan

Keyword(s):

Magnetic Field ◽

Viscoelastic Properties ◽

Frequency Dependent ◽

Stiffness Method ◽

The Magnetic Field ◽

Dynamic Blocked Transfer Stiffness

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Investigation of the Compressive Viscoelastic Properties of Brain Tissue Under Time and Frequency Dependent Loading Conditions

Annals of Biomedical Engineering ◽

10.1007/s10439-021-02866-0 ◽

2021 ◽

Author(s):

Weiqi Li ◽

Duncan E. T. Shepherd ◽

Daniel M. Espino

Keyword(s):

Finite Element ◽

Brain Tissue ◽

Time Domain ◽

Viscoelastic Properties ◽

Loss Modulus ◽

Series Representation ◽

Experimental Tests ◽

Finite Element Models ◽

Frequency Dependent

AbstractThe mechanical characterization of brain tissue has been generally analyzed in the frequency and time domain. It is crucial to understand the mechanics of the brain under realistic, dynamic conditions and convert it to enable mathematical modelling in a time domain. In this study, the compressive viscoelastic properties of brain tissue were investigated under time and frequency domains with the same physical conditions and the theory of viscoelasticity was applied to estimate the prediction of viscoelastic response in the time domain based on frequency-dependent mechanical moduli through Finite Element models. Storage and loss modulus were obtained from white and grey matter, of bovine brains, using dynamic mechanical analysis and time domain material functions were derived based on a Prony series representation. The material models were evaluated using brain testing data from stress relaxation and hysteresis in the time dependent analysis. The Finite Element models were able to represent the trend of viscoelastic characterization of brain tissue under both testing domains. The outcomes of this study contribute to a better understanding of brain tissue mechanical behaviour and demonstrate the feasibility of deriving time-domain viscoelastic parameters from frequency-dependent compressive data for biological tissue, as validated by comparing experimental tests with computational simulations.

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Effect of Degradation and Osteoarthritis on the Viscoelastic Properties of Human Knee Articular Cartilage: An Experimental Study and Constitutive Modeling

Biomechanics ◽

10.3390/biomechanics1020019 ◽

2021 ◽

Vol 1 (2) ◽

pp. 225-238

Author(s):

Hesam Khajehsaeid ◽

Zanko Abdollahpour ◽

Hedyeh Farahmandpour

Keyword(s):

Articular Cartilage ◽

Mechanical Behavior ◽

Energy Absorption ◽

Tissue Damage ◽

Viscoelastic Properties ◽

Viscoelastic Model ◽

Absorption Capacity ◽

Model Parameters ◽

Human Knee ◽

Nonlinear Viscoelastic Model

Articular cartilage, as a hydrated soft tissue which covers diarthrodial joints, has a pivotal role in the musculoskeletal system. Osteoarthritis is the most common degenerative disease that affects most individuals over the age of 55. This disease affects the elasticity, lubrication mechanism, damping function, and energy absorption capability of articular cartilage. In order to investigate the effect of osteoarthritis on the performance of articular cartilage, the mechanical behavior of human knee articular cartilage was experimentally investigated. Progressive cyclic deformation was applied beyond the physiological range to facilitate degradation of the tissue. The relaxation response of the damaged tissue was modeled by means of a fractional-order nonlinear viscoelastic model in the framework of finite deformations. It is shown that the proposed fractional model well reproduces the tissue’s mechanical behavior using a low number of parameters. Alteration of the model parameters was also investigated throughout the progression of tissue damage. This helps predict the mechanical behavior of the osteoarthritic tissue based on the level of previous damage. It is concluded that, with progression of osteoarthritis, the articular cartilage loses its viscoelastic properties such as damping and energy absorption capacity. This is also accompanied by a loss of stiffness which deteriorates more rapidly than viscosity does throughout the evolution of tissue damage. These results are thought to be significant in better understanding the degradation of articular cartilage and the progression of OA, as well as in the design of artificial articular cartilages.

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Targeted Loss of Proteoglycans Results in Changes of Frequency-Dependent Viscoelastic Behavior of the Intact Articular Cartilage

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80869 ◽

2012 ◽

Author(s):

Simon Y. Tang ◽

Tamara Alliston

Keyword(s):

Articular Cartilage ◽

Mechanical Behavior ◽

Viscoelastic Behavior ◽

Enzymatic Digestion ◽

Cartilage Tissue ◽

Indentation Modulus ◽

Frequency Dependent ◽

Bovine Articular Cartilage ◽

Before And After ◽

Tan Δ

Cartilage is a multi-phasic, viscoelastic material that derives its mechanical behavior of its primary constituents including collagen, proteoglycans, and water. The complex mechanical function of cartilage depends critically on the composition and balance of these constituents. We sought to determine the effects of proteoglycan loss on both the time- and frequency-dependent mechanical behavior of articular cartilage. Using cathepsin d, an enzyme that specifically cleaves proteoglycans, we assessed the in situ mechanical behavior of intact bovine articular cartilage before and after enzymatic digestion using microindentation over loading frequencies ranging between 0.5 hz to 20 hz. The loss of proteoglycans does not affect the elastic components of mechanical behavior (indentation modulus; p = 0.67), but have significant consequences on the viscoelastic components (tan δ; p<0.001). Moreover, the changes in the viscoelastic mechanical behavior are more pronounced at higher loading frequencies (p<0.001). Taken together, these results suggest that proteoglycans are critical for providing dynamic stability for the cartilage tissue.

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Noise Reduction Evaluation of Multi-Layered Viscoelastic Infinite Cylinder under Acoustical Wave Excitation

Shock and Vibration ◽

10.1155/2008/930746 ◽

2008 ◽

Vol 15 (5) ◽

pp. 551-572 ◽

Cited By ~ 4

Author(s):

M.R. Mofakhami ◽

H. Hosseini Toudeshky ◽

Sh. Hosseini Hashemi

Keyword(s):

Noise Reduction ◽

Viscoelastic Material ◽

Viscoelastic Properties ◽

Separation Of Variables ◽

Theory Of Elasticity ◽

Acoustic Medium ◽

Viscoelastic Layer ◽

Infinite Cylinder ◽

Frequency Dependent ◽

Uniform Noise

In this paper sound transmission through the multilayered viscoelastic air filled cylinders subjected to the incident acoustic wave is studied using the technique of separation of variables on the basis of linear three dimensional theory of elasticity. The effect of interior acoustic medium on the mode maps (frequency vs geometry) and noise reduction is investigated. The effects of internal absorption and external moving medium on noise reduction are also evaluated. The dynamic viscoelastic properties of the structure are rigorously taken into account with a power law technique that models the viscoelastic damping of the cylinder. A parametric study is also performed for the two layered infinite cylinders to obtain the effect of viscoelastic layer characteristics such as thickness, material type and frequency dependency of viscoelastic properties on the noise reduction. It is shown that using constant and frequency dependent viscoelastic material with high loss factor leads to the uniform noise reduction in the frequency domain. It is also shown that the noise reduction obtained for constant viscoelastic material property is subjected to some errors in the low frequency range with respect to those obtained for the frequency dependent viscoelastic material.Noise reduction analyses are also performed for the infinite cylinder subjected to the periodic incident wave with uniform and piecewise form.

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