On the wave propagation properties and Poisson’s ratio of the Star-3/6 structures

2021 ◽  
pp. 114089
Author(s):  
Pengcheng Zhao ◽  
Kai Zhang ◽  
Cheng Zhao ◽  
Zichen Deng
Keyword(s):  
Wave Propagation ◽  
Poisson’S Ratio ◽  
Poisson's Ratio ◽  
Propagation Properties

Effect of longitudinal stress on wave propagation in width-constrained elastic plates with arbitrary Poisson's ratio

2015 ◽  
Vol 252 (7) ◽  
pp. 1615-1619 ◽  
Author(s):  
Paweł Sobieszczyk ◽  
Marcin Majka ◽  
Dominika Kuźma ◽  
Teik-Cheng Lim ◽  
Piotr Zieliński
Keyword(s):  
Wave Propagation ◽  
Poisson’S Ratio ◽  
Poisson's Ratio ◽  
Elastic Plates ◽  
Longitudinal Stress

P-SV wave propagation in heterogeneous media: Velocity‐stress finite‐difference method

Geophysics ◽  
1986 ◽  
Vol 51 (4) ◽  
pp. 889-901 ◽  
Author(s):  
Jean Virieux
Keyword(s):  
Wave Propagation ◽  
Poisson’S Ratio ◽  
Heterogeneous Media ◽  
Velocity Dispersion ◽  
Poisson's Ratio ◽  
S Wave ◽  
Phase Velocity Dispersion ◽  
Wave Phase Velocity ◽  
Converted Phases ◽  
Phase Velocity Dispersion Curve

I present a finite‐difference method for modeling P-SV wave propagation in heterogeneous media. This is an extension of the method I previously proposed for modeling SH-wave propagation by using velocity and stress in a discrete grid. The two components of the velocity cannot be defined at the same node for a complete staggered grid: the stability condition and the P-wave phase velocity dispersion curve do not depend on the Poisson’s ratio, while the S-wave phase velocity dispersion curve behavior is rather insensitive to the Poisson’s ratio. Therefore, the same code used for elastic media can be used for liquid media, where S-wave velocity goes to zero, and no special treatment is needed for a liquid‐solid interface. Typical physical phenomena arising with P-SV modeling, such as surface waves, are in agreement with analytical results. The weathered‐layer and corner‐edge models show in seismograms the same converted phases obtained by previous authors. This method gives stable results for step discontinuities, as shown for a liquid layer above an elastic half‐space. The head wave preserves the correct amplitude. Finally, the corner‐edge model illustrates a more complex geometry for the liquid‐solid interface. As the Poisson’s ratio v increases from 0.25 to 0.5, the shear converted phases are removed from seismograms and from the time section of the wave field.

scholarly journals Wave Propagation in Auxetic Tetrachiral Honeycombs

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
K. F. Tee ◽  
A. Spadoni ◽  
F. Scarpa ◽  
M. Ruzzene
Keyword(s):  
Wave Propagation ◽  
Poisson’S Ratio ◽  
Bloch Wave ◽  
Unit Cell ◽  
Poisson's Ratio ◽  
Flexural Wave ◽  
Negative Poisson’S Ratio ◽  
Representative Unit Cell ◽  
Negative Poisson's Ratio ◽  
Phase Constant

This paper describes a numerical and experimental investigation on the flexural wave propagation properties of a novel class of negative Poisson’s ratio honeycombs with tetrachiral topology. Tetrachiral honeycombs are structures defined by cylinders connected by four tangent ligaments, leading to a negative Poisson’s ratio (auxetic) behavior in the plane due to combined cylinder rotation and bending of the ribs. A Bloch wave approach is applied to the representative unit cell of the honeycomb to calculate the dispersion characteristics and phase constant surfaces varying the geometric parameters of the unit cell. The modal density of the tetrachiral lattice and of a sandwich panel having the tetrachiral as core is extracted from the integration of the phase constant surfaces, and compared with the experimental ones obtained from measurements using scanning laser vibrometers.

Longitudinal Wave Velocity in Auxetic Rods

2015 ◽  
Vol 137 (2) ◽  
Author(s):  
Teik-Cheng Lim
Keyword(s):  
Wave Propagation ◽  
Longitudinal Wave ◽  
Wave Velocity ◽  
Poisson’S Ratio ◽  
Propagation Model ◽  
Poisson's Ratio ◽  
Longitudinal Wave Velocity ◽  
Compressive Wave ◽  
Elementary Wave ◽  
Wave Propagation Model

This short brief develops a model for the velocity of longitudinal wave propagation in auxetic rods. Due to the large density change in auxetic solids and significant lateral deformation for Poisson's ratio between −1 and −0.5, this note takes into consideration density correction and lateral inertia. Results show that deviation from the elementary wave propagation model becomes more significant the more the Poisson's ratio of the rod material deviates from 1/4, in which the deviation of wave velocity is insignificant for Poisson's ratio in the positive range, but significant in the negative range. Specifically, the tensile and compressive wave velocity increases and decreases, respectively, for Poisson's ratio less than 1/4, but this trend reverses for Poisson's ratio greater than 1/4. In addition to showing that the elementary wave propagation model is invalid for describing the longitudinal wave velocity in auxetic rods, the results also suggest that auxetic materials are useful for applications that require slowing down and speeding up of compressive and tensile wave propagations, respectively.

Harnessing uniaxial tension to tune Poisson's ratio and wave propagation in soft porous phononic crystals: an experimental study

Soft Matter ◽  
2019 ◽  
Vol 15 (14) ◽  
pp. 2921-2927 ◽  
Author(s):  
Nan Gao ◽  
Jian Li ◽  
Rong-hao Bao ◽  
Wei-qiu Chen
Keyword(s):  
Experimental Study ◽  
Wave Propagation ◽  
Uniaxial Tension ◽  
Poisson’S Ratio ◽  
Phononic Crystal ◽  
Phononic Crystals ◽  
Band Gaps ◽  
Poisson's Ratio ◽  
Elliptical Holes

In this work, we investigate the effect of regulation of uniaxial tension on the band gaps in 2D soft phononic crystal with criss-crossed elliptical holes via experiments.

The Model for Calculating Elastic Modulus and Poisson's Ratio of Coal Body

2013 ◽  
Vol 6 (1) ◽  
pp. 36-43 ◽  
Author(s):  
Ai Chi ◽  
Li Yuwei
Keyword(s):  
Elastic Modulus ◽  
Poisson’S Ratio ◽  
Fractured Rock ◽  
Rock Block ◽  
Poisson's Ratio ◽  
Linear Elastic ◽  
Study Results ◽  
The Face ◽  
Block Face ◽  
Coal Rock

Coal body is a type of fractured rock mass in which lots of cleat fractures developed. Its mechanical properties vary with the parametric variation of coal rock block, face cleat and butt cleat. Based on the linear elastic theory and displacement equivalent principle and simplifying the face cleat and butt cleat as multi-bank penetrating and intermittent cracks, the model was established to calculate the elastic modulus and Poisson's ratio of coal body combined with cleat. By analyzing the model, it also obtained the influence of the parameter variation of coal rock block, face cleat and butt cleat on the elastic modulus and Poisson's ratio of the coal body. Study results showed that the connectivity rate of butt cleat and the distance between face cleats had a weak influence on elastic modulus of coal body. When the inclination of face cleat was 90°, the elastic modulus of coal body reached the maximal value and it equaled to the elastic modulus of coal rock block. When the inclination of face cleat was 0°, the elastic modulus of coal body was exclusively dependent on the elastic modulus of coal rock block, the normal stiffness of face cleat and the distance between them. When the distance between butt cleats or the connectivity rate of butt cleat was fixed, the Poisson's ratio of the coal body initially increased and then decreased with increasing of the face cleat inclination.

Sign in / Sign up

Export Citation Format

Share Document