Atomistic simulations on the mechanical properties of silicene nanoribbons under uniaxial tension

The periodically distributed fracture spacing phenomenon exists in the failure process of the reinforced concrete prism under uniaxial tension. In this paper, A numerical code RFPA3D (3D Realistic Failure Process Analysis) is used to simulate the three-dimensional failure process of plain concrete prism specimen and reinforced concrete prism specimen under uniaxial tension. The reinforced concrete is represented by a set of elements with same size and different mechanical properties. They are uniform cubic elements and their mechanical properties, including elastic modulus and peak strength, are distributed through the specimens according to a certain statistical distribution. The elastic modulus and other mechanical properties are weakened gradually when the stresses in the elements meet the specific failure criterion. The displacement-controlled loading scheme is used to simulate the complete failure process of reinforced concrete. The analyses focus on the failure mechanisms of the concrete and reinforcement. The complete process of the fracture for the plain concrete prism and the fracture initiation, infilling and saturation of the reinforced concrete prism is reproduced. It agrees well with the theoretical analysis. Through 3D numerical tests for the specimen, it can be investigated the interaction between the reinforcement and concrete mechanical properties in meso-level and the numerical code is proved to be an effective way to help thoroughly understand the rule of the reinforcement and concrete and also help the design of the structural concrete components and systems.

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Mechanical response of bilayer silicene nanoribbons under uniaxial tension

RSC Advances ◽

10.1039/c7ra12482a ◽

2018 ◽

Vol 8 (20) ◽

pp. 10785-10793 ◽

Cited By ~ 2

Author(s):

M. R. Chávez-Castillo ◽

M. A. Rodríguez-Meza ◽

L. Meza-Montes

Keyword(s):

Stress Distribution ◽

Uniaxial Tension ◽

Mechanical Response ◽

Silicene Nanoribbons

Ghost vacancy effect on the stress distribution of bilayer silicene nanoribbons.

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Length Scale Effects in Materials Deformation of Nano and Microscale Au Structures

Volume 11: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2009-12077 ◽

2009 ◽

Author(s):

Jie Lian ◽

Junlan Wang

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Size Effect ◽

Sample Size ◽

Atomistic Simulation ◽

Scale Effects ◽

Elastic Recovery ◽

Boundary Effect ◽

Dislocation Nucleation ◽

Atomistic Simulations

In this study, intrinsic size effect — strong size dependence of mechanical properties — in materials deformation was investigated by performing atomistic simulation of compression on Au (114) pyramids. Sample boundary effect — inaccurate measurement of mechanical properties when sample size is comparable to the indent size — in nanoindentation was also investigated by performing experiments and atomistic simulations of nanoindentation into nano- and micro-scale Au pillars and bulk Au (001) surfaces. For intrinsic size effect, dislocation nucleation and motions that contribute to size effect were analyzed for studying the materials deformation mechanisms. For sample boundary effect, in both experiments and atomistic simulation, the elastic modulus decreases with increasing indent size over sample size ratio. Significantly different dislocation motions contribute to the lower value of the elastic modulus measured in the pillar indentation. The presence of the free surface would allow the dislocations to annihilate, causing a higher elastic recovery during the unloading of pillar indentation.

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Effect of Cold Storage on Mechanical Properties of Aorta

Volume 9: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2015-51610 ◽

2015 ◽

Author(s):

Shijia Zhao ◽

John Lof ◽

Shelby Kutty ◽

Linxia Gu

Keyword(s):

Mechanical Properties ◽

Uniaxial Tension ◽

Cold Storage ◽

Elastic Moduli ◽

Heart Diseases ◽

Axial Direction ◽

Circumferential Direction ◽

Control Group ◽

Aortic Tissue ◽

Tension Tests

Aortic allografts have been widely used in treatments of congenital heart diseases with satisfactory clinical outcomes. They were usually cryopreserved and stored for surgical use. The objective of this work was to investigate the effect of cold storage on mechanical properties of aorta, since the compliance mismatch was one important factor associated with the complication after graft surgery. The segments of porcine descending aorta were divided into two groups: the fresh samples which were tested within 24 hours after harvesting served as control group, and frozen samples which were stored in −20°C for 7 days and then thawed. The uniaxial tension tests along circumferential direction and indentation tests were conducted. The average incremental elastic moduli within each stretch range were obtained from the experimental data obtained during tension tests, and the elastic moduli were also calculated by fitting the force-indentation depth data to Hertz model when the tissue was stretched at 1.0, 1.2, 1.4 and 1.6. In addition, the average incremental elastic moduli of both fresh and frozen aortic tissue along axial direction were also obtained by using uniaxial tension tests. The comparison showed that cold storage definitely increased the average incremental elastic modulus of the aortic tissue along circumferential direction; however, the difference is not significant for the elastic moduli along axial direction.

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Mechanical properties of tantalum carbide from high-pressure/high-temperature synthesis and first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06819h ◽

2020 ◽

Vol 22 (9) ◽

pp. 5018-5023 ◽

Cited By ~ 2

Author(s):

Weiguo Sun ◽

Xiaoyu Kuang ◽

Hao Liang ◽

Xinxin Xia ◽

Zhengang Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

High Pressure ◽

First Principles ◽

Tantalum Carbide ◽

Atomistic Simulations ◽

First Principles Calculations ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

High Pressure High Temperature ◽

Deformation Models

The mechanical strength of ceramic material TaC can be described well with atomistic simulations if realistic deformation models are considered.

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Hierarchical Structure and Properties of Graphene Oxide Papers

Journal of Applied Mechanics ◽

10.1115/1.4024177 ◽

2013 ◽

Vol 80 (4) ◽

Cited By ~ 9

Author(s):

Charles D. Wood ◽

Marc J. Palmeri ◽

Karl W. Putz ◽

Zhi An ◽

SonBinh T. Nguyen ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Structural Feature ◽

Uniaxial Tension ◽

Hierarchical Structure ◽

Mechanical Response ◽

Structure And Properties ◽

Fracture Surfaces ◽

High Stiffness ◽

Significant Attention

The mechanical properties of graphene oxide papers have attracted significant attention in recent years due to their high stiffness and tough behavior. While the structural feature most commonly characterized is the nanosheet spacing, there is a hierarchical structure, which is likely responsible for the impressive mechanical properties. In this paper, we examine the structure of graphene oxide papers on several length scales using novel techniques to distinguish between lamellae and a newly defined feature, termed “super-lamellae.” The differentiation between these intermediate features provides context to the previously observed mechanical response and fracture surfaces of graphene oxide papers, particularly under uniaxial tension.

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