Mechanical Behavior of Irregular Fibers. Part I: Modeling the Tensile Behavior of Linear Elastic Fibers

The present work investigates the vibrational properties of a DNA-like structure by means of a harmonic Hamiltonian and the Green’s function formalism. The DNA sequence is considered as a quasi one-dimensional system in which the mass-spring pairs are randomly distributed inside each crystalline unit. The sizes of the units inside the system are increased, in a step-by-step approach, so that the actual condition of the DNA could be modeled more accurately. The linear-elastic forces mimicking the bonds between the pairs are initially considered constant along the entire length of the system. In the next step, these forces are randomly shuffled so as to take into account the inherent randomness of the DNA. The results reveal that increasing the number of mass-spring pairs in the crystalline structure decreases the influence of randomness on the mechanical behavior of the structure. This also holds true for systems with larger crystalline units. The obtained results can be used to investigate the mechanical behavior of similar macro-systems.

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A numerical and experimental study on the tensile behavior of plasma shocked granite under dynamic loading

Rakenteiden Mekaniikka ◽

10.23998/rm.65301 ◽

2017 ◽

Vol 50 (2) ◽

pp. 41-62

Author(s):

Ahmad Mardoukhi ◽

Timo Saksala ◽

Mikko Hokka ◽

Veli-Tapani Kuokkala

Keyword(s):

Experimental Study ◽

Tensile Strength ◽

Mechanical Behavior ◽

Thermal Shock ◽

Dynamic Loading ◽

Split Hopkinson Pressure Bar ◽

Tensile Behavior ◽

Brazilian Disc ◽

Brazilian Disc Test ◽

Plasma Shock

This paper presents a numerical and experimental study on the mechanical behavior of plasma shocked rock. The dynamic tensile behavior of plasma shock treated Balmoral Red granite was studied under dynamic loading using the Brazilian disc test and the Split Hopkinson Pressure Bar device. Different heat shocks were produced on the Brazilian disc samples by moving the plasma gun over the sample at different speeds. Microscopy clearly showed that as the duration of the thermal shock increases, the number of the surface cracks and their complexity increases (quantified here as the fractal dimension of the crack patterns) and the area of the damaged surface grows larger as well. At the highest thermal shock duration of 0.80 seconds the tensile strength of the Brazilian disc sample drops by approximately 20%. In the numerical simulations of the dynamic Brazilian disc test, this decrease in tensile strength was reproduced by modeling the plasma shock induced damage using the embedded discontinuity finite element method. The damage caused by the plasma shock was modeled by two methods, namely by pre-embedded discontinuity populations with zero strength and by assuming that the rock strength is lowered and conform to the Weibull distribution. This paper presents a quantitative assessment of the effects of the heat shock, the surface microstructure and mechanical behavior of the studied rock, and a promising numerical model to account for the pre-existing crack distributions in a rock material.

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Effect of Process Orientation on the Mechanical Behavior and Piezoelectricity of Electroactive Paper

Materials ◽

10.3390/ma13010204 ◽

2020 ◽

Vol 13 (1) ◽

pp. 204

Author(s):

Sean Yoon ◽

Jung Woong Kim ◽

Hyun Chan Kim ◽

Jaehwan Kim

Keyword(s):

Mechanical Behavior ◽

Process Orientation ◽

Linear Elastic ◽

Strong Shear ◽

Performance Deterioration ◽

Alignment Angle ◽

Anisotropic Elastic ◽

Stretching Ratio ◽

Orientation Dependency ◽

Piezoelectric Charge

This paper reports the effect of process orientation on the mechanical behavior and piezoelectricity of electroactive paper (EAPap) made from natural cotton pulp. EAPap is fabricated by a casting and wet drawing of cellulose film after dissolving cotton with LiCl and DMAc solvent. During the fabrication, permanent wrinkles, a possible factor for performance deterioration, were found in the films. Finite element method was introduced to identify the formation mechanism behind the wrinkles. The simulation results show that the wrinkles were caused by buckling and are inevitable under any conditions. The tensile and piezoelectric tests show that the orientation dependency of the stretched EAPap gives the anisotropic characteristics on both mechanical and piezoelectric properties. In this research, the anisotropic elastic moduli and Poisson’s ratios are reported. The piezoelectric charge constant of EAPap in the linear elastic is calculated. The piezoelectric charge constants of EAPap are associated with the alignment angle in the order of 45° > 0° > 90° due to the strong shear effect. The higher stretching ratio gives the higher piezoelectricity due to the alignment of the molecular chains and the microstructure in EAPap. The highest piezoelectric charge constant is found to be 12 pC/N at a stretching ratio of 1.6 and aligning angle of 45°.

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Mechanical behavior of ballasted railway track stabilized with polyurethane: A finite element analysis

MATEC Web of Conferences ◽

10.1051/matecconf/201825104056 ◽

2018 ◽

Vol 251 ◽

pp. 04056 ◽

Cited By ~ 1

Author(s):

Zelimkhan Khakiev ◽

Alexander Kruglikov ◽

Georgy Lazorenko ◽

Anton Kasprzhitskii ◽

Yakov Ermolov ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Mechanical Behavior ◽

Finite Element Simulation ◽

Elasticity Modulus ◽

Railway Track ◽

Binding Agent ◽

Element Analysis ◽

Linear Elastic ◽

Element Simulation

Analysis of mechanical behavior of ballast shoulder of railway track reinforced by polyurethane binding agent has been performed by the method of finite-element simulation Limitation of the model of linear-elastic properties of geocomposite has been displayed. Dependence of elasticity modulus of geocomposite on deformation value has been suggested. Influence of penetration depth of polyurethane binding agent on behavior of railway track construction under different train loads has been studied.

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Elastic Fibers and Large Artery Mechanics in Animal Models of Development and Disease

Journal of Biomechanical Engineering ◽

10.1115/1.4038704 ◽

2018 ◽

Vol 140 (2) ◽

Cited By ~ 9

Author(s):

Maria Gabriela Espinosa ◽

Marius Catalin Staiculescu ◽

Jungsil Kim ◽

Eric Marin ◽

Jessica E. Wagenseil

Keyword(s):

Animal Models ◽

Mechanical Behavior ◽

Computational Models ◽

Mechanical Response ◽

Elastic Fiber ◽

High Stress ◽

Elastic Fibers ◽

Large Artery ◽

Fiber Network ◽

Pulsatile Pressure

Development of a closed circulatory system requires that large arteries adapt to the mechanical demands of high, pulsatile pressure. Elastin and collagen uniquely address these design criteria in the low and high stress regimes, resulting in a nonlinear mechanical response. Elastin is the core component of elastic fibers, which provide the artery wall with energy storage and recoil. The integrity of the elastic fiber network is affected by component insufficiency or disorganization, leading to an array of vascular pathologies and compromised mechanical behavior. In this review, we discuss how elastic fibers are formed and how they adapt in development and disease. We discuss elastic fiber contributions to arterial mechanical behavior and remodeling. We primarily present data from mouse models with elastic fiber deficiencies, but suggest that alternate small animal models may have unique experimental advantages and the potential to provide new insights. Advanced ultrastructural and biomechanical data are constantly being used to update computational models of arterial mechanics. We discuss the progression from early phenomenological models to microstructurally motivated strain energy functions for both collagen and elastic fiber networks. Although many current models individually account for arterial adaptation, complex geometries, and fluid–solid interactions (FSIs), future models will need to include an even greater number of factors and interactions in the complex system. Among these factors, we identify the need to revisit the role of time dependence and axial growth and remodeling in large artery mechanics, especially in cardiovascular diseases that affect the mechanical integrity of the elastic fibers.

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Numerical simulation of tensile behavior of corroded aluminum alloy 2024 T3

International Journal of Structural Integrity ◽

10.1108/ijsi-10-2014-0050 ◽

2015 ◽

Vol 6 (4) ◽

pp. 451-467 ◽

Cited By ~ 4

Author(s):

Dorothea Setsika ◽

Konstantinos Tserpes ◽

Spiros Pantelakis

Keyword(s):

Aluminum Alloy ◽

Mechanical Behavior ◽

Corrosion Damage ◽

Exposure Period ◽

Tensile Specimen ◽

Tensile Behavior ◽

Content Type ◽

Structural Part ◽

Representative Unit Cell ◽

Aluminum Alloy 2024

Purpose – The purpose of this paper is to develop a multi-scale modeling approach for simulating the tensile behavior of corroded aluminum alloy 2024 T3. Design/methodology/approach – The approach combines two FE models: a model of a three-dimensional representative unit cell representing a pit and a model of the tensile specimen. The models lie at the micro- and macro-scales, respectively. The local homogenized mechanical behavior of the corroded material is simulated for different pit configurations. Then, the behavior of the pits is introduced into different areas (elements) of the tensile specimen and final analyses are performed to simulate the mechanical behavior of the corroded material. The approach has been applied to six different exposure periods of the exfoliation corrosion test. Findings – The numerical results show that the presence of pits and exfoliated areas reduces the yield strength of the material. The comparison of predicted elongation to fracture with the experimental of each exposure period value allows for the indirect assessment of the effect of hydrogen embrittlement. Originality/value – Since the characteristics of corrosion damage evolution with exposure time are constant for the specific material, the model could be applied for the simulation of the mechanical behavior of any corroded structural part (e.g. a mechanically fastened panel) made from the aluminum 2024 T3 alloy.

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Mechanical Behavior of Fracture Filled with Variable Medium

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.2203 ◽

2012 ◽

Vol 472-475 ◽

pp. 2203-2206

Author(s):

Jin Gang Chen ◽

Na Chen ◽

Jun Li Yang

Keyword(s):

Mechanical Behavior ◽

Laboratory Experiments ◽

Behavior Model ◽

Flow State ◽

Linear Elastic ◽

Ideal Plastic ◽

Strain Data ◽

Variable Medium ◽

Normal Compression ◽

The Ideal

Filled fracture is a fracture in which sands or other materials occupy some void spaces. This study uses well-controlled laboratory experiments to investigate mechanical behavior of fracture filled with variable medium by means of normal compression and lateral restraint. A large number of stress-strain data are obtained. The mechanical behavior of filled fracture with variable medium can be divided into three phases: rheological phase, compaction phase and linear elastic phase. At the beginning of the experiment, the filled fracture is in the ideal plastic flow state. The overall strength of filled fracture increase with finite deformation and normal stress increasing, and show linear elastic characters. Based on the experiment results and characteristics, the mechanical behavior model of fracture filled with variable medium is constructed, and also its mechanism is analyzed.

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A state-of-the art review of tensile behavior of the textile-reinforced concrete composite

Transport and Communication Science Journal ◽

10.47869/tcsj.72.1.14 ◽

2021 ◽

Vol 72 (1) ◽

pp. 127-142

Author(s):

Tien Tran Manh ◽

Tu Do Ngoc ◽

Hong Vu Xuan

Keyword(s):

Reinforced Concrete ◽

Mechanical Behavior ◽

State Of The Art ◽

Experimental Studies ◽

Tensile Behavior ◽

Fiber Reinforced Polymer ◽

Textile Reinforced Concrete ◽

Characterization Methods ◽

Reinforced Polymer ◽

Strain Hardening Behavior

Over the past two decades, textile-reinforced concrete (TRC) materials have been increasingly and widely used for the strengthening/reinforcement of civil engineering works. Thanks to their many advantages as the durability, considerable bond strength with the reinforced concrete (RC) members, best recycling conditions, the TRC materials are considered as an optimal alternative solution to substitute the traditional strengthening and reinforcing materials FRP (Fiber-Reinforced Polymer). The mechanical behavior of TRC composite has been characterized in previous experimental studies. This paper presents a state-of-the-art review of the mechanical behavior of TRC composite under tensile loading. By inheriting from previous review studies, this paper updates the experimental studies on the tensile behavior of TRC composite in the last decade. The review addresses, firstly the mechanical properties of constituent materials in TRC as reinforcement textile, cementitious matrix, and textile/matrix interface. Secondly, it addresses the tensile behavior of TRC composite, including the characterization methods as well as analyses of its strain-hardening behavior with different phases. The paper then discusses the main factors which influence the mechanical behavior of TRC materials in the available experimental studies. Finally, the conclusion of this review terminates this paper.

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ANÁLISE DO COMPORTAMENTO MECÂNICO DE MACIÇOS ROCHOSOS CONTENDO DESCONTINUIDADES ATRAVÉS DO MÉTODO DAS DIFERENÇAS FINITAS VIA IMPLEMENTAÇÃO COMPUTACIONAL [ Analysis of the mechanical behavior of rocky mass with discontinuities through the finite differences method via computational implementation ]

REEC - Revista Eletrônica de Engenharia Civil ◽

10.5216/reec.v15i1.51157 ◽

2018 ◽

Vol 15 (1) ◽

Author(s):

Luma Alvarenga Carvalho de Vasconcelos ◽

Pedro Guilherme Cipriano Silva ◽

Pedro Ivo Amaro Alves

Keyword(s):

Rock Mass ◽

Mechanical Behavior ◽

Numerical Solutions ◽

Compressive Force ◽

Shear Stiffness ◽

Relative Displacement ◽

Shear Stresses ◽

Linear Elastic ◽

Finite Differences Method ◽

Fortran 90

RESUMO: Neste trabalho é realizada uma análise computacional por meio da resolução de equações diferenciais para a modelagem de soluções analíticas e numéricas (MDF) do comportamento mecânico de um maciço rochoso contendo descontinuidades. Realizou-se simulações adotando um bloco composto por um material homogêneo, isotrópico e linear elástico sob atuação de uma força externa compressiva aplicada na sua extremidade livre e confinado entre duas descontinuidades rígidas, nas superfícies inferior e superior. A descontinuidade inferior apresenta rugosidade, caracterizada por um módulo de rigidez ao cisalhamento que conduz a uma distribuição de tensão cisalhante e a um deslocamento relativo entre o bloco e a base. Os resultados foram gerados através da compilação dos dados no programa computacional FORTRAN 90, e, com isso, pode-se verificar o deslocamento relativo entre o bloco e a descontinuidade, bem como as tensões atuantes em cada ponto previamente definido; e ainda realizar uma comparação entre as soluções analítica e numérica. Como principal contribuição do trabalho para a área da geotecnia, cita-se a possibilidade de uma análise de deslocamento de descontinuidades presentes em maciços rochosos mais próxima da realidade já que considera o meio como descontínuo. Além disso apresenta-se uma solução computacional de fácil implementação e entendimento.ABSTRACT: In this work a computational analysis is performed by solving differential equations for the modeling of numerical (MDF) and analytical solutions of the mechanical behavior of a rock mass with discontinuities. Simulations were carried out by adopting a block composed of a homogeneous, isotropic and linear elastic material under the action of an external compressive force applied at its free end and confined between two rigid discontinuities on the lower and upper surfaces. The lower discontinuity presents roughness characterized by a shear stiffness modulus leading to a shear stress distribution and a relative displacement between the block and the base. The results were generated through the compilation of the data in the FORTRAN 90 computer program, and with this, it is possible to verify the relative displacement between the block and the discontinuity, as well as the shear stresses acting at each previously defined point; and also perform a comparison between analytical and numerical solutions. The main contribution of the work to the area of geotechnics is the possibility of an analysis of discontinuity displacement present in rock mass closer to reality since it considers the environment as discontinuous. In addition, a computational solution is presented that is easy to implement and understand.

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Investigating mechanical properties of 3D printed parts manufactured in different orientations on Multijet printer

10.21203/rs.3.rs-247844/v1 ◽

2021 ◽

Author(s):

Ramesh Chand ◽

Vishal S Sharma ◽

Trehan Rajeev

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Mechanical Behavior ◽

Polymer Material ◽

Polymeric Materials ◽

Tensile Behavior ◽

Jet Printing ◽

3D Printed

Abstract Polymer material based products in the engineering field are most widely produced by the multi jet printing (MJP). These products impart inherent benefits in manufacturing intricate contours and shapes at less additional expenses. This emphasizes the importance of studying the mechanical behavior of the manufactured parts, using polymeric materials in different orientations. In this investigation density, tensile behavior & hardness were studied for 3D-printed parts produced in four different orientations (A, B, C and D). It is found that for the best mechanical properties part should be fabricated using orientation ‘A’. Furthermore, for density and tensile strength part should not be fabricated using orientation ‘C’. Also in case of hardness part should not be fabricated in orientation ‘B’.

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