The Postbuckling Behavior of Compressed Elastica Inside a Flexible Tube: Experimental and Numerical Investigation

2021 ◽  
pp. 1-44
Author(s):  
Yossi Dayan ◽  
David Durban ◽  
Sefi Givli
Keyword(s):  
Elastic Fiber ◽  
Practical Importance ◽  
Compressive Force ◽  
Quantitative Information ◽  
Postbuckling Behavior ◽  
Flexible Tube ◽  
Buckling Behavior ◽  
Wide Range ◽  
Depth Analysis ◽  
Post Buckling

Abstract The post-buckling behavior of an elastic fiber subjected to lateral constraints is of practical importance in a wide range of medical and engineering applications. The vast majority of existing studies have adopted the assumption that the lateral constrains are fixed in space and rigid. This assumption is often far from the reality of the physical complexity of the abovementioned systems. In this paper, we study analytically, numerically, and experimentally, the behavior of an elastic fiber that is subjected to compressive force and constrained by a flexible tube. The latter marks a point of departure from available research. Our experiments provide quantitative information related to the overall behavior of the system, like force-shortening relation and deflection of the flexible tube. That information is complemented by finite-element simulations that enable in-depth analysis of the deformation of the fiber as well as contact characteristics between the fiber and the inner wall of the flexible tube. Finally, a simple mathematical model, aimed at providing analytical insights, is presented. Overall, the theoretical, numerical, and experimental results are in very good agreement. They highlight the fact that the behavior of a compressed fiber that is constrained by a deformable tube significantly deviates from that of a fiber constrained inside a rigid cylinder. Moreover, it is shown that the overall behavior as well as the evolution of contact between the fiber and the cylinder heavily depend on the ratio between the stiffness of the fiber and the lateral stiffness of the tube.

The Postbuckling Behavior of Planar Elastica Constrained by a Deformable Wall

2017 ◽  
Vol 84 (5) ◽  
Author(s):  
Shmuel Katz ◽  
Sefi Givli
Keyword(s):  
Mode Switching ◽  
Careful Examination ◽  
Postbuckling Behavior ◽  
Contact Conditions ◽  
Practical Applications ◽  
Buckling Behavior ◽  
Wide Range ◽  
Compliant Wall ◽  
Post Buckling ◽  
The Mathematical Model

Attributed to its significance in a wide range of practical applications, the post-buckling behavior of a beam with lateral constraints has drawn much attention in the last few decades. Despite the fact that, in reality, the lateral constraints are often flexible or deformable, vast majority of studies have considered fixed and rigid lateral constraints. In this paper, we make a step toward bridging this gap by studying the post-buckling behavior of a planar beam that is laterally constrained by a deformable wall. Unfortunately, the interaction with a compliant wall prevents derivation of closed-form analytical solutions. Nevertheless, careful examination of the governing equations of a simplified model reveals general properties of the solution, and let us identify the key features that govern the behavior. Specifically, we construct universal “solution maps” that do not depend on the mode number and enable simple and easy prediction of the contact conditions and of the mode-switching force (the force at which the system undergoes instantaneous transition from one equilibrium configuration (or mode) to another). The predictions of the mathematical model are validated against finite element (FE) simulations.

Buckling and Post Buckling Behavior of a Transversely Stiffened Ship Hull Model

1964 ◽  
Vol 8 (04) ◽  
pp. 7-21
Author(s):  
H.G. Schultz
Keyword(s):  
Reasonable Agreement ◽  
Ship Hull ◽  
Buckling Load ◽  
Experimental Results ◽  
Postbuckling Behavior ◽  
Pure Bending ◽  
Box Girder ◽  
Buckling Behavior ◽  
Theoretical Investigations ◽  
Post Buckling

In the paper presented the behavior of a transversely formed box-girder model subjected to pure bending is discussed, where the deck plating of the model is loaded above the buckling load. The experimental results obtained are in reasonable agreement with theoretical investigations and show the influence of fabrication initiated plate deflections on the buckling and postbuckling behavior of the deck plating clearly. A method is suggested for determining the buckling load of plates having large initial deformations.

POST-BUCKLING OF AN ELASTIC COLUMN WITH VARIOUS ROTATIONAL END RESTRAINTS

2005 ◽  
Vol 05 (01) ◽  
pp. 113-123 ◽  
Author(s):  
B. PHUNGPAINGAM ◽  
S. CHUCHEEPSAKUL
Keyword(s):  
Shooting Method ◽  
Nonlinear Differential Equations ◽  
Compressive Force ◽  
Limit Load ◽  
Technical Note ◽  
Buckling Behavior ◽  
End Conditions ◽  
Post Buckling ◽  
Secondary Bifurcation ◽  
Elastic Column

In this technical note, the post-buckling behavior of a simply supported elastic column with various rotational end conditions of the supports is investigated. The compressive force is applied at the tip of the column. The characteristic equation for solving the critical loads is obtained from the boundary value problem of linear systems. In the post-buckling state, a set of nonlinear differential equations with boundary conditions is established and numerically solved by the shooting method. The interesting features associated with this problem such as the limit load point, snap-through phenomenon and the secondary bifurcation point will be highlighted herein.

Buckling and Postbuckling Behavior of Clamped Shallow Spherical Shells Under Axisymmetric Ring Loads

1971 ◽  
Vol 38 (4) ◽  
pp. 996-1002 ◽  
Author(s):  
N. Akkas ◽  
N. R. Bauld
Keyword(s):  
Numerical Study ◽  
Postbuckling Behavior ◽  
Spherical Shells ◽  
Concentrated Load ◽  
Fixed Ring ◽  
Buckling Behavior ◽  
Load Carrying ◽  
Post Buckling ◽  
Shell Parameter ◽  
Shell Geometry

This paper presents the results of a numerical study of the buckling and initial post-buckling behavior of clamped shallow spherical shells under axisymmetric ring loads. This behavior is studied for a cap with fixed geometry when the location of the ring load is allowed to vary from the equivalent of a concentrated load at the apex to a location near the midpoint of the shell base radius, and for a fixed ring load location when the shell geometry is allowed to vary. It is found in both studies that a significant range of the geometric shell parameter λ exists such that buckling is accompanied by a loss in load-carrying capacity.

Diversity and Integration in Private International Law

2019 ◽  
Keyword(s):  
South America ◽  
International Law ◽  
Value Systems ◽  
Private International Law ◽  
Diverse Range ◽  
Cross Border ◽  
Wide Range ◽  
Depth Analysis ◽  
And Shifts ◽  
Substantive Law

This book opens a cross-regional dialogue and shifts the Eurocentric discussion on diversity and integration to a more inclusive engagement with South America in private international law issues. It promotes a contemporary vision of private international law as a discipline enabling legal interconnectivity, with the potential to transcend its disciplinary boundaries to further promote the reality of cross-border integration, with its focus on the ever-increasing cross-border mobility of individuals. Private international law embraces legal diversity and pluralism. Different legal traditions continue to meet, interact and integrate in different forms, at the national, regional and international levels. Different systems of substantive law couple with divergent systems of private international law (designed to accommodate the former in cross-border situations). This complex legal landscape impacts individuals and families in cross-border scenarios, and international commerce broadly conceived. Private international law methodologies and techniques offer means for the coordination of this constellation of legal orders and value systems in cross-border situations. Bringing together world-renowned academics and experienced private international lawyers from a wide range of jurisdictions in Europe and South America, this edited collection focuses on the connective capabilities of private international law in bridging and balancing legal diversity as a corollary for the development of integration. The book provides in-depth analysis of the role of private international law in dealing with legal diversity across a diverse range of topics and jurisdictions.

Buckling Behavior of Tire Breaker Structure

1983 ◽  
Vol 11 (1) ◽  
pp. 3-19
Author(s):  
T. Akasaka ◽  
S. Yamazaki ◽  
K. Asano
Keyword(s):  
Elastic Foundation ◽  
Elastic Moduli ◽  
Wave Length ◽  
Bending Moment ◽  
Experimental Results ◽  
Automobile Tire ◽  
Buckling Behavior ◽  
Post Buckling ◽  
Steel Cord ◽  
Interlaminar Shear

Abstract The buckled wave length and the critical in-plane bending moment of laminated long composite strips of cord-reinforced rubber sheets on an elastic foundation is analyzed by Galerkin's method, with consideration of interlaminar shear deformation. An approximate formula for the wave length is given in terms of cord angle, elastic moduli of the constituent rubber and steel cord, and several structural dimensions. The calculated wave length for a 165SR13 automobile tire with steel breakers (belts) was very close to experimental results. An additional study was then conducted on the post-buckling behavior of a laminated biased composite beam on an elastic foundation. This beam is subjected to axial compression. The calculated relationship between the buckled wave rise and the compressive membrane force also agreed well with experimental results.

scholarly journals Detectivity optimization to detect of ultraweak light fluxes with an EM-CCD as binary photon counter array

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ibtissame Khaoua ◽  
Guillaume Graciani ◽  
Andrey Kim ◽  
François Amblard
Keyword(s):  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Photon Counting ◽  
Detection Methods ◽  
Strong Nonlinearity ◽  
Wide Range ◽  
Depth Analysis ◽  
Spatially Extended ◽  
Extended Sources ◽  
Photon Counting Mode

AbstractFor a wide range of purposes, one faces the challenge to detect light from extremely faint and spatially extended sources. In such cases, detector noises dominate over the photon noise of the source, and quantum detectors in photon counting mode are generally the best option. Here, we combine a statistical model with an in-depth analysis of detector noises and calibration experiments, and we show that visible light can be detected with an electron-multiplying charge-coupled devices (EM-CCD) with a signal-to-noise ratio (SNR) of 3 for fluxes less than $$30\,{\text{photon}}\,{\text{s}}^{ - 1} \,{\text{cm}}^{ - 2}$$ 30 photon s - 1 cm - 2 . For green photons, this corresponds to 12 aW $${\text{cm}}^{ - 2}$$ cm - 2 ≈ $$9{ } \times 10^{ - 11}$$ 9 × 10 - 11 lux, i.e. 15 orders of magnitude less than typical daylight. The strong nonlinearity of the SNR with the sampling time leads to a dynamic range of detection of 4 orders of magnitude. To detect possibly varying light fluxes, we operate in conditions of maximal detectivity $${\mathcal{D}}$$ D rather than maximal SNR. Given the quantum efficiency $$QE\left( \lambda \right)$$ Q E λ of the detector, we find $${ \mathcal{D}} = 0.015\,{\text{photon}}^{ - 1} \,{\text{s}}^{1/2} \,{\text{cm}}$$ D = 0.015 photon - 1 s 1 / 2 cm , and a non-negligible sensitivity to blackbody radiation for T > 50 °C. This work should help design highly sensitive luminescence detection methods and develop experiments to explore dynamic phenomena involving ultra-weak luminescence in biology, chemistry, and material sciences.

scholarly journals Quantitative linear dichroism imaging of molecular processes in living cells made simple by open software tools

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Alexey Bondar ◽  
Olga Rybakova ◽  
Josef Melcr ◽  
Jan Dohnálek ◽  
Petro Khoroshyy ◽  
...  
Keyword(s):  
Biological Systems ◽  
Linear Dichroism ◽  
Quantitative Information ◽  
Living Cells ◽  
Software Tools ◽  
Model Systems ◽  
Membrane Properties ◽  
Polarization Microscopy ◽  
Molecular Processes ◽  
Wide Range

AbstractFluorescence-detected linear dichroism microscopy allows observing various molecular processes in living cells, as well as obtaining quantitative information on orientation of fluorescent molecules associated with cellular features. Such information can provide insights into protein structure, aid in development of genetically encoded probes, and allow determinations of lipid membrane properties. However, quantitating and interpreting linear dichroism in biological systems has been laborious and unreliable. Here we present a set of open source ImageJ-based software tools that allow fast and easy linear dichroism visualization and quantitation, as well as extraction of quantitative information on molecular orientations, even in living systems. The tools were tested on model synthetic lipid vesicles and applied to a variety of biological systems, including observations of conformational changes during G-protein signaling in living cells, using fluorescent proteins. Our results show that our tools and model systems are applicable to a wide range of molecules and polarization-resolved microscopy techniques, and represent a significant step towards making polarization microscopy a mainstream tool of biological imaging.

Appraisal of Allowable Loads by Simplified Rules

1986 ◽  
Vol 108 (2) ◽  
pp. 131-137
Author(s):  
D. Moulin
Keyword(s):  
Experimental Investigation ◽  
Plastic Region ◽  
Thin Structures ◽  
Geometric Imperfections ◽  
Buckling Behavior ◽  
Simplified Method ◽  
Post Buckling ◽  
Initial Geometric Imperfections ◽  
Fast Breeder Reactors ◽  
Breeder Reactors

This paper presents a simplified method to analyze the buckling of thin structures like those of Liquid Metal Fast Breeder Reactors (LMFBR). The method is very similar to those used for the buckling of beams and columns with initial geometric imperfections, buckling in the plastic region. Special attention is paid to the strain hardening of material involved and to possible unstable post-buckling behavior. The analytical method uses elastic calculations and diagrams that account for various initial geometric defects. An application of the method is given. A comparison is made with an experimental investigation concerning a representative LMFBR component.

Sign in / Sign up

Export Citation Format

Share Document