scholarly journals Large-Strain Hyperelastic Constitutive Model of Envelope Material under Biaxial Tension with Different Stress Ratios

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1780 ◽  
Author(s):  
Zhipeng Qu ◽  
Wei He ◽  
Mingyun Lv ◽  
Houdi Xiao
Keyword(s):  
Constitutive Model ◽  
Stress Ratio ◽  
Biaxial Tension ◽  
Large Strain ◽  
Tensile Failure ◽  
Biaxial Tensile ◽  
Envelope Material ◽  
Fiber Matrix ◽  
Stress Ratios ◽  
Fiber Interaction

This paper reports the biaxial tensile mechanical properties of the envelope material through experimental and constitutive models. First, the biaxial tensile failure tests of the envelope material with different stress ratio in warp and weft directions are carried out. Then, based on fiber-reinforced continuum mechanics theory, an anisotropic hyperelastic constitutive model on envelope material with different stress ratio is developed. A strain energy function that characterizes the anisotropic behavior of the envelope material is decomposed into three parts: fiber, matrix and fiber–fiber interaction. The fiber–matrix interaction is eliminated in this model. A new simple model for fiber–fiber interaction with different stress ratio is developed. Finally, the results show that the constitutive model has a good agreement with the experiment results. The results can be used to provide a reference for structural design of envelope material.

A critical-state constitutive model for liquefiable sand

2005 ◽  
Vol 42 (3) ◽  
pp. 830-855 ◽  
Author(s):  
SM Reza Imam ◽  
Norbert R Morgenstern ◽  
Peter K Robertson ◽  
David H Chan
Keyword(s):  
Constitutive Model ◽  
Critical State ◽  
Stress Ratio ◽  
Large Strain ◽  
Triaxial Compression ◽  
Loose Sand ◽  
Inherent Anisotropy ◽  
Dense Sand ◽  
Peak Point ◽  
Wide Range

This paper presents a critical-state constitutive model for sands over a wide range of void ratios and consolidation pressures in a triaxial plane. A single set of parameters, including a unique critical-state line reached at large strain, is also used in the model, and differences in behavior in triaxial compression and extension are modeled by accounting for anisotropy at small and medium ranges of strain. The model uses a capped yield surface (YS), which is characterized by its size and shape. Following evidence in past literature, the stress ratio at the peak point of the capped YS of loose sands is approximated by the stress ratio measured at the peak point of their undrained effective stress path. Yielding parameters obtained using this stress ratio are also applied in modeling dense sand behavior and drained loading. These parameters account for the effects of inherent anisotropy, void ratio, and confining pressure on yielding stresses and are readily determined from laboratory tests, but further research is required on their determination from field data. The model accounts for stress-induced and inherent anisotropies, using different parameters, which develop and evolve independently. Emphasis is placed on proper modeling of aspects of loose sand behavior that affect their susceptibility to flow liquefaction.Key words: constitutive modeling, liquefaction, loose sand, critical state, dilatancy, hardening.

In Situ Stress Measurement Method Based on X-Ray Diffraction under Biaxial Tensile Loading

2011 ◽  
Vol 675-677 ◽  
pp. 615-618
Author(s):  
Dong Ying Ju ◽  
J.G. Wang ◽  
Minoru Abe
Keyword(s):  
Stress Distribution ◽  
Applied Stress ◽  
Stress Measurement ◽  
Biaxial Tension ◽  
Crack Tip ◽  
Tension Test ◽  
X Ray Diffraction ◽  
X Ray ◽  
Biaxial Tensile ◽  
Stress Ratios

The purpose of this investigation is to detect damage from stress distribution in the surface of near pre-crack tip by using X-ray diffraction technique during biaxial tension test. An measurements apparatus to measure stress distribution along pre-crack direction was fabrication by use of a biaxial tensile test device and a stress analyzer based on single exposure technique with one position sensitive proportional counter. Stress distribution with different tensile applied stress ratios were measured during biaxial tension test. As results, the shape of actual stress was keeping increase with increasing tensile applied stress. At maximum applied stress, the residual stress increases with the increasing distance from the crack tip; after reaching a maximum it gradually diminish.

An Anisotropic Hyperelastic Constitutive Model With Fiber-Matrix Shear Interaction for the Human Annulus Fibrosus

2005 ◽  
Vol 73 (5) ◽  
pp. 815-824 ◽  
Author(s):  
X. Q. Peng ◽  
Z. Y. Guo ◽  
B. Moran
Keyword(s):  
Constitutive Model ◽  
Energy Function ◽  
Annulus Fibrosus ◽  
Strain Energy ◽  
Strain Energy Function ◽  
Material Parameters ◽  
The Matrix ◽  
Fiber Matrix ◽  
Matrix Shear ◽  
Fiber Interaction

Based on fiber reinforced continuum mechanics theory, an anisotropic hyperelastic constitutive model for the human annulus fibrosus is developed. A strain energy function representing the anisotropic elastic material behavior of the annulus fibrosus is additively decomposed into three parts nominally representing the energy contributions from the matrix, fiber and fiber-matrix shear interaction, respectively. Taking advantage of the laminated structure of the annulus fibrosus with one family of aligned fibers in each lamella, interlamellar fiber-fiber interaction is eliminated, which greatly simplifies the constitutive model. A simple geometric description for the shearing between the fiber and the matrix is developed and this quantity is used in the representation of the fiber-matrix shear interaction energy. Intralamellar fiber-fiber interaction is also encompassed by this interaction term. Experimental data from the literature are used to obtain the material parameters in the constitutive model and to provide model validation. Determination of the material parameters is greatly facilitated by the partition of the strain energy function into matrix, fiber and fiber-matrix shear interaction terms. A straightforward procedure for computation of the material parameters from simple experimental tests is proposed.

An anisotropic hyperelastic constitutive model for plain weave fabric considering biaxial tension coupling

2017 ◽  
Vol 89 (3) ◽  
pp. 434-444 ◽  
Author(s):  
Yuan Yao ◽  
Xiaoshuang Huang ◽  
Xiongqi Peng ◽  
Pengfei Liu ◽  
Gong Youkun
Keyword(s):  
Experimental Data ◽  
Constitutive Model ◽  
Coupling Effect ◽  
Biaxial Tension ◽  
Numerical Results ◽  
Material Parameter Identification ◽  
Forming Simulation ◽  
Plain Weave ◽  
Biaxial Tensile ◽  
Weave Fabric

A nonlinear anisotropic hyperelastic constitutive model is developed for plain weave fabrics by considering biaxial tensile coupling. The strain energy function is decomposed into two parts to represent tensile energy, including the biaxial tensile coupling effect from fiber elongation and shearing energy from relative rotation between warp and weft yarns. A simple and efficient material parameter identification method is proposed. The model is exemplified on a balanced plain weave glass fabric. Experimental data from the literature are used to identify material parameters in the constitutive model. Model validation is implemented by comparing numerical results with various experimental data, including biaxial tension tests under different stretch ratios and the picture frame shearing test. The developed constitutive model is applied to numerical simulation of a double-dome stamping of the plain weave fabric. The influences of binder force and initial fiber yarn orientation on forming are investigated. Numerical results demonstrated that the biaxial tensile coupling effect could not be neglected in forming simulation. The developed constitutive model is suitable to characterize the nonlinear behavior of plain weave fabrics under large deformation.

Biaxial tensile failure of short carbon-fibre-reinforced PEEK composites

2021 ◽  
pp. 108764
Author(s):  
Huaipu Kang ◽  
Lin Qi ◽  
Haoyuan Dang ◽  
Kanghua Jin ◽  
Daniel Thomson ◽  
...  
Keyword(s):  
Carbon Fibre ◽  
Tensile Failure ◽  
Biaxial Tensile ◽  
Short Carbon

scholarly journals Numerical simulation on the simultaneous stress interference of parallel multiple hydraulic fractures

2021 ◽  
pp. 014459872110019
Author(s):  
Weiyong Lu ◽  
Changchun He
Keyword(s):  
Principal Stress ◽  
Hydraulic Fracture ◽  
Stress Ratio ◽  
Fracture Network ◽  
Hydraulic Fractures ◽  
Fracture Spacing ◽  
Induced Stress ◽  
Minimum Principal Stress ◽  
Fracturing Process ◽  
Stress Ratios

During horizontal well staged fracturing, there is stress interference between multiple transverse fractures in the same perforation cluster. Theoretical analysis and numerical calculation methods are applied in this study. We analysed the mechanism of induced stress interference in a single fracture under different fracture spacings and principal stress ratios. We also investigated the hydraulic fracture morphology and synchronous expansion process under different fracture spacings and principal stress ratios. The results show that the essence of induced stress is the stress increment in the area around the hydraulic fracture. Induced stress had a dual role in the fracturing process. It created favourable ground stress conditions for the diversion of hydraulic fractures and the formation of complex fracture network systems, inhibited fracture expansion in local areas, stopped hydraulic fractures, and prevented the formation of effective fractures. The curves of the maximum principal stress, minimum principal stress, and induced principal stress difference with distance under different fracture lengths, different fracture spacings, and different principal stress ratios were consistent overall. With a small fracture spacing and a small principal stress ratio, intermediate hydraulic fractures were difficult to initiate or arrest soon after initiation, fractures did not expand easily, and the expansion speed of lateral hydraulic fractures was fast. Moreover, with a smaller fracture spacing and a smaller principal stress ratio, hydraulic fractures were more prone to steering, and even new fractures were produced in the minimum principal stress direction, which was beneficial to the fracture network communication in the reservoir. When the local stress and fracture spacing were appropriate, the intermediate fracture could expand normally, which could effectively increase the reservoir permeability.

The Further Exploration of Applying Small-Strain and Large-Strain Formulations to SMA

2012 ◽  
Vol 529 ◽  
pp. 228-235
Author(s):  
Jie Yao ◽  
Yong Hong Zhu
Keyword(s):  
Phase Transformation ◽  
Constitutive Model ◽  
Uniaxial Tension ◽  
Driving Force ◽  
Research Team ◽  
Large Strain ◽  
Small Deformation ◽  
Small Strain ◽  
Proportional Loading ◽  
The Difference

Recently, our research team has been considering to applying shape memory alloys (SMA) constitutive model to analyze the large and small deformation about the SMA materials because of the thermo-dynamics and phase transformation driving force. Accordingly, our team use simulations method to illustrate the characteristics of the model in large strain deformation and small strain deformation when different loading, uniaxial tension, and shear conditions involve in the situations. Furthermore, the simulation result unveils that the difference is nuance concerning the two method based on the uniaxial tension case, while the large deformation and the small deformation results have huge difference based on shear deformation case. This research gives the way to the further research about the constitutive model of SMA, especially in the multitiaxial non-proportional loading aspects.

Cumulative Damage in Fatigue under Multiaxial Stress Conditions

1974 ◽  
Vol 188 (1) ◽  
pp. 423-430 ◽  
Author(s):  
D. L. Mcdiarmid
Keyword(s):  
Experimental Investigation ◽  
Aluminium Alloy ◽  
Principal Stress ◽  
Stress Ratio ◽  
Uniaxial Stress ◽  
Cumulative Damage ◽  
Stress Conditions ◽  
Multiaxial Stress ◽  
Stress Ratios ◽  
Damage Criteria

Previous investigations into cumulative damage fatigue under uniaxial stress are discussed in conjunction with the parameters relevant to the present experimental investigation. The results of two-level block programme tests on 2L65 aluminium alloy at four values of constant principal stress ratio and at several combinations of two different principal stress ratios are presented and discussed with reference to cumulative damage criteria developed for the case of uniaxial fatigue stress.

Small strain stiffness for granite residual soil: effect of stress ratio

2021 ◽  
Author(s):  
Xianwei Zhang ◽  
Xinyu Liu ◽  
Lingwei Kong ◽  
Gang Wang ◽  
Cheng Chen
Keyword(s):  
Stress Ratio ◽  
Small Strain ◽  
Residual Soil ◽  
Resonant Column ◽  
Residual Soils ◽  
Column Tests ◽  
Small Strain Stiffness ◽  
Deviator Stress ◽  
Granite Residual Soil ◽  
Stress Ratios

Most previous studies have focused on the small strain stiffness of sedimentary soil while little attention has been given to residual soils with different properties. Most studies also neglected the effects of the deviator stress, which is extensively involved in civil engineering. This note considers the effects of the deviator stress on the small-strain stiffness of natural granite residual soil (GRS) as established from resonant column tests performed under various stress ratios. Although increasing the stress ratio results in a greater maximum shear modulus for both natural and remolded residual soils, remolded soil is more sensitive to changes in the stress ratio, which highlights the effects of soil cementation. The data herein offers new insights to understand the stiffness of residual soil and other weathered geomaterials.

An experimental study on the uniaxial and biaxial flexural tensile strength of concrete

1983 ◽  
Vol 10 (1) ◽  
pp. 104-115
Author(s):  
Zenon A. Zielinski ◽  
Ioanis Spiropoulos
Keyword(s):  
Tensile Strength ◽  
Biaxial Tension ◽  
Concrete Strength ◽  
Uniaxial Stress ◽  
Bottom Surface ◽  
Test Results ◽  
Flexural Tensile Strength ◽  
Modes Of Failure ◽  
Biaxial Tensile ◽  
Support Conditions

The flexural uniaxial and biaxial tensile strength of concrete was studied experimentally on one-way and two-way ribbed slab specimens. The specimens, consisting of a thin slab and deep ribs, constituted part of a waffle-like structure.Uniaxial tension was achieved by supporting the specimens at two points at the ends of one rib, and biaxial tension by supporting the specimens at four points at the ends of two cross ribs. In both support conditions, load was applied in the middle of the slab, thus introducing flexural tension in the ribs and compression in the slab.Measurements of tensile strain were carried out by means of uniaxial strain gauges attached to the bottom surface of the ribs. The modes of failure of concrete in uniaxial and biaxial tension were observed and are discussed in this paper. A revised biaxial failure envelope of concrete in tension is proposed.The test results indicate that the tensile strength of concrete is about 38% higher in the uniaxial stress state than in the biaxial. Keywords: concrete strength, uniaxial and biaxial tensile flexural strength, maximum strains, cracking, ribbed structure, waffle structure.

Sign in / Sign up

Export Citation Format

Share Document