Derived Interaction Parameters for the TSAI-WU Tensor Polynomial Theory of Strength for Composite Materials

Mapping Intimacies ◽

10.1115/imece2001/amd-25417 ◽

2001 ◽

Author(s):

Steven J. DeTeresa ◽

Gregory J. Larsen

Keyword(s):

Hydrostatic Pressure ◽

Fiber Composite ◽

Strength Criterion ◽

Test Methods ◽

Standard Test ◽

Transverse Compression ◽

Strength Parameters ◽

Carbon Fiber Composite ◽

The Stability ◽

Stability Limits

Abstract It is shown that the two interactive strength parameters in the Tsai-Wu tensor polynomial strength criterion for fiber composites can be derived in terms of the uniaxial or non-interacting strength parameters if the composite does not fail under practical levels of hydrostatic pressure or equal transverse compression. Thus the required number of parameters is reduced from seven to five and all five of the remaining strength terms are easily determined using standard test methods. The derived interactive parameters fall within the stability limits of the theory, yet they lead to open failure surfaces in the compressive stress quadrant. The assumptions used to derive the interactive parameters were supported by measurements for the effect of hydrostatic pressure and unequal transverse compression on the behavior of a typical carbon fiber composite.

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Study on Post-Failure Deformation and Residual Strength of Rock Mass Based on Hoek-Brown Criterion

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.121 ◽

2012 ◽

Vol 170-173 ◽

pp. 121-124

Author(s):

Jian Xin Han ◽

Xing Hua Tong ◽

Lei Wang ◽

Guo Fu Sun

Keyword(s):

Rock Mass ◽

Residual Strength ◽

Strain Softening ◽

Strain Curve ◽

Strength Criterion ◽

Stress Strain Curve ◽

Strength Parameters ◽

Softening Parameter ◽

Residual Values ◽

The Stability

In order to predict the stability of surrounding rock mass in geotechnical engineering, it is important to study the post-failure deformation property and residual strength of rock mass. Based on evolutional behavior of strength parameters, aiming at generalized Hoek-Brown strength criterion, selecting major principal strain as strain softening parameter, this paper presents the method of solving post-failure stress-strain curve . In numerical case, the effect of evolutional law of strength parameters ， and to deformation and residual strength is discussed and we can draw the following conclusions: the greater the residual values of ， are and the smaller the residual value of is, the post-failure strain softening curve falls more gently and the greater the residual strength is.

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Determination of Mohr–Coulomb Parameters from Nonlinear Strength Criteria for 3D Slopes

Mathematical Problems in Engineering ◽

10.1155/2019/6927654 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Di Wu ◽

Yuke Wang ◽

Yue Qiu ◽

Juan Zhang ◽

Yukuai Wan

Keyword(s):

Optimization Procedure ◽

Strength Criterion ◽

Friction Angle ◽

Strength Parameters ◽

Strength Criteria ◽

Engineering Standards ◽

3D Effects ◽

Software Codes ◽

The Stability

Many experimental data have illustrated that the strength envelops for soils are not linear. Nevertheless, the linear Mohr–Coulomb (MC) strength parameters are widely applied for the conventional method, software codes, and engineering standards in the slope design practice. Hence, this paper developed the 3D limit analysis for the stability of soil slopes with the nonlinear strength criterion. Based on a numerical optimization procedure written in Matlab software codes, the equivalent MC parameters (the equivalent friction angle and the equivalent cohesion) from the nonlinear strength envelopes were derived with respect to the least upper-bound solutions. Further investigations were made to assess the influences of nonlinear strength parameters and slope geometries on the equivalent MC parameters. The presented results indicate that the equivalent MC parameters are closely related to the nonlinear strength parameters. As the inclination angle increases, the equivalent friction angle becomes bigger, but the equivalent cohesion becomes smaller. Besides, 3D effects on the equivalent MC parameters were found to be slight. The presented approach for the determination of MC strength parameters is analytical and rigorous, and the approximate MC strength parameters in the provided design tables can be alternative references for practical use.

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The standard strength test of 3D printing materials and its application for UAV propellers

Modern Physics Letters B ◽

10.1142/s0217984920400175 ◽

2020 ◽

Vol 34 (07n09) ◽

pp. 2040017

Author(s):

Yung-Lan Yeh

Keyword(s):

Composite Material ◽

Carbon Fiber ◽

3D Printing ◽

Fused Deposition Modeling ◽

Fiber Composite ◽

Standard Test ◽

Future Application ◽

Carbon Fiber Composite ◽

Fiber Composite Material ◽

Fused Deposition

This study investigates the possibility analysis of UAV propeller made by commercial 3D printing machine. The primary experimental facility is 3D printer based on Fused Deposition Modeling method (FDM). The main methodology of this work is to construct standard test piece according to ASTM standard and use for standard test. The Polylactic Acid (PLA) and carbon fiber composite material are the main two printing materials in this work. Experimental results reveal that the strength and bending of these two materials are enough to be the propeller of middle size UAV, especially the carbon fiber composite material. This study not only confirms the application possibility of UAV propeller made by 3D printing, but also carries out the real flight test to identify performance enhancement and future application.

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Optimization of the Material of External Fixator with FEM Simulation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.919.275 ◽

2018 ◽

Vol 919 ◽

pp. 275-281

Author(s):

Filip Tomanec ◽

Soňa Rusnáková ◽

Milan Žaludek

Keyword(s):

Carbon Fiber ◽

External Fixator ◽

Fiber Composite ◽

Fem Simulation ◽

Finite Element Method Simulation ◽

Carbon Fiber Composite ◽

Final Model ◽

Material Development ◽

Design Changes ◽

The Stability

Patients and surgeons with tibia fracture using external fixator are worried about a higher weight of metal fixator´s construction and therefore also poor manipulation ability with this tool [1]. During the last few years the bone tissue engineering has improved significantly and along with that also material development has increased [2,3]. Therefore patients requirements can be achieved by optimizing the material composition of this product. The main objective of this research is a weight reduction by material and design changes of the external fixator. Another aim is the evaluation of the final model. The model of innovative fixator was created and also computed in software CATIA V5-6 using finite element method simulation. Appropriate forces were applied and the simulation was performed. Results of FEM simulation indicate that the final weight of complete product declined significantly after application of carbon-fiber composite. Test results also suggest that the rigidity and the stability of complete fixator are safe. Hence this research describes that application of carbon fiber composite into the external fixator design is an important improvement of the external fixator.

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Synthetic hydroxyapatite and its use in bioactive coatings

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800018817463 ◽

2019 ◽

Vol 17 (1) ◽

pp. 228080001881746 ◽

Cited By ~ 1

Author(s):

Luis Daniel Guillen-Romero ◽

Mercedes Teresita Oropeza-Guzmán ◽

Eduardo Alberto López-Maldonado ◽

Ana Leticia Iglesias ◽

Juan Antonio Paz-González ◽

...

Keyword(s):

Fiber Composite ◽

Colloidal Suspensions ◽

X Ray Diffraction ◽

Carbon Fiber Composite ◽

Bioactive Coatings ◽

Composite Surface ◽

Bone Injury ◽

Different Temperatures ◽

Injury Treatment ◽

The Stability

An approach to solve the limitations of autologous bone grafting procedures in bone injury treatment is to develop bioactive coatings in the implantation system. The objective of this work is to compare the temperature effect on the stability of hydroxyapatite, graphene, and collagen colloidal suspensions to be used as biocompatible and bioactive coatings on a carbon fiber composite surface. Synthesized hydroxyapatite was assessed by X-ray diffraction. Zeta potential at different temperatures was evaluated. Specimens were characterized using scanning electron microscopy and Raman analysis. The results showed that the best hydroxyapatite/graphene ratio was 85/15, while those of the hydroxyapatite/collagen mixtures were 85/15. A hydroxyapatite/graphene/collagen mixture was synthesized based on these results.

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