Stress-strain relationship for empirical equations of creep in rocks

Glulam bamboo has been preliminarily explored for use as a structural building material, and its stress–strain model under axial loading has a fundamental role in the analysis of bamboo components. To study the tension and compression behaviour of glulam bamboo, the bamboo scrimber and laminated bamboo as two kinds of typical glulam bamboo materials were tested under axial loading. Their mechanical behaviour and failure modes were investigated. The results showed that the bamboo scrimber and laminated bamboo have similar failure modes. For tensile failure, bamboo fibres were ruptured with sawtooth failure surfaces shown as brittle failure; for compression failure, the two modes of compression are buckling and compression shear failure. The stress–strain relationship curves of the bamboo scrimber and laminated bamboo are also similar. The tensile stress–strain curves showed a linear relationship, and the compressive stress–strain curves can be divided into three stages: elastic, elastoplastic and post-yield. Based on the test results, the stress–strain model was proposed for glulam bamboo, in which a linear equation was used to describe the tensile stress–strain relationship and the Richard–Abbott model was employed to model the compressive stress–strain relationship. A comparison with the experimental results shows that the predicted results are in good agreement with the experimental curves.

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Evaluation of the stress-strain relationship in the high strain region of high strength materials by using the shear stretch test

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/967/1/012050 ◽

2020 ◽

Vol 967 ◽

pp. 012050

Author(s):

Y Taguchi ◽

Y Maeda ◽

Y Maeda

Keyword(s):

High Strain ◽

High Strength ◽

Stress Strain ◽

Strain Relationship

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Semi-inverse method for predicting stress–strain relationship from cone indentations

Journal of Materials Research ◽

10.1557/jmr.2003.0291 ◽

2003 ◽

Vol 18 (9) ◽

pp. 2068-2078 ◽

Cited By ~ 20

Author(s):

A. DiCarlo ◽

H. T. Y. Yang ◽

S. Chandrasekar

Keyword(s):

A Priori ◽

Model Material ◽

Material Behavior ◽

The Finite Element Method ◽

Stress Strain ◽

Indentation Tests ◽

Strain Relationship ◽

Initial Force ◽

Relationship Of ◽

Force Displacement

A method for determining the stress–strain relationship of a material from hardness values H obtained from cone indentation tests with various apical angles is presented. The materials studied were assumed to exhibit power-law hardening. As a result, the properties of importance are the Young's modulus E, yield strength Y, and the work-hardening exponent n. Previous work [W.C. Oliver and G.M. Pharr, J. Mater. Res. 7, 1564 (1992)] showed that E can be determined from initial force–displacement data collected while unloading the indenter from the material. Consequently, the properties that need to be determined are Y and n. Dimensional analysis was used to generalize H/E so that it was a function of Y/E and n [Y-T. Cheng and C-M. Cheng, J. Appl. Phys. 84, 1284 (1999); Philos. Mag. Lett. 77, 39 (1998)]. A parametric study of Y/E and n was conducted using the finite element method to model material behavior. Regression analysis was used to correlate the H/E findings from the simulations to Y/E and n. With the a priori knowledge of E, this correlation was used to estimate Y and n.

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