Browsing by Author "Hsieh, HY"

Now showing 1 - 3 of 3

Direct tensile behavior of a transversely isotropic rock
(1997-07-01)
Liao, JJ
;
Yang, MT
;
Hsieh, HY
;
土木工程學系
;
Department of Civil Engineering
The tensile behavior of a transversely isotropic rock is investigated by a series of direct tensile tests on cylindrical argillite specimens. To study the deformability of argillite under tension, two components of an electrically resistant type of strain gage with a parallel arrangement, or a semiconductor strain gage, are adopted for measuring the small transverse strain observed on specimens during testing. The curves of axial stress vs axial strain and vs average volumetric strain ape presented for argillite specimens with differently inclined angles of foliation. Experimental results indicate that the stress-strain behavior depends on the foliation inclination of specimens with respect to the loading direction. The five elastic constants of argillite are calculated by measuring two cylindrical specimens in the manner recommended by Wei and Hudson. Based on theoretical analysis results, the range of the foliation inclination of the specimens tested is investigated for feasibility obtaining the Jive elastic moduli. A dipping angle of the foliations (theta) of 30-60 degrees with respect to the plane normal to the loading direction is recommended. The final failure modes of the specimens are investigated in detail. A sawtoothed failure plane occurs for the specimens with a high inclination of foliation with respect to the plane perpendicular to the loading direction. On the other hand, a smooth plane occurs along the foliation for specimens with low inclination of foliation with respect to the plane normal to the loading direction. A conceptual failure criterion of tensile strength is proposed for specimens with a high inclination of foliation. (C) 1997 Elsevier Science Ltd.
Direct tensile behavior of a transversely isotropic rock
(1997-07-01)
Liao, JJ
;
Yang, MT
;
Hsieh, HY
;
交大名義發表
;
土木工程學系
The tensile behavior of a transversely isotropic rock is investigated by a series of direct tensile tests on cylindrical argillite specimens. To study the deformability of argillite under tension, two components of an electrically resistant type of strain gage with a parallel arrangement, or a semiconductor strain gage, are adopted for measuring the small transverse strain observed on specimens during testing. The curves of axial stress vs axial strain and vs average volumetric strain ape presented for argillite specimens with differently inclined angles of foliation. Experimental results indicate that the stress-strain behavior depends on the foliation inclination of specimens with respect to the loading direction. The five elastic constants of argillite are calculated by measuring two cylindrical specimens in the manner recommended by Wei and Hudson. Based on theoretical analysis results, the range of the foliation inclination of the specimens tested is investigated for feasibility obtaining the Jive elastic moduli. A dipping angle of the foliations (theta) of 30-60 degrees with respect to the plane normal to the loading direction is recommended. The final failure modes of the specimens are investigated in detail. A sawtoothed failure plane occurs for the specimens with a high inclination of foliation with respect to the plane perpendicular to the loading direction. On the other hand, a smooth plane occurs along the foliation for specimens with low inclination of foliation with respect to the plane normal to the loading direction. A conceptual failure criterion of tensile strength is proposed for specimens with a high inclination of foliation. (C) 1997 Elsevier Science Ltd.
Triaxial residual strength of an anisotropic rock
(1999)
Liao, JJ
;
Hsieh, HY
;
土木工程學系
;
Department of Civil Engineering
Peak strength and its failure criteria of anisotropic rocks have been studied and reported. However, few publications referred to residual strength behavior of anisotropic rocks.;A laboratory testing technique, called the multiple failure state of triaxial test, was adopted to evaluate the residual strength behavior of anisotropic rocks in triaxial compression. A series of tests was performed on core samples of argillite. The experimental results show the fact that the triaxial residual strength is directly related to the inclination angle of specimen foliation with respect to the axial loading direction. The minimum triaxial residual strength occurs in the specimen with 30 degrees of inclination angle; and specimens with 0 degrees or 90 degrees inclination have maximum triaxial residual strength. Analyzing the experimental data by the basis of the Mohr-Coulomb failure criterion, the residual cohesive strength strongly depends on the inclination of foliation. Nevertheless, the residual friction angle is independent of the inclination of foliation. A new failure criterion of triaxial residual strength for anisotropic rocks, modified from the Hoek and Brown failure criterion, is proposed in this paper. The criterion correlates closely with the experimental data of argillite specimens and can be extended to estimate the triaxial residual strength for inherent anisotropic rocks with discontinuities.