Modified Equivalent Radius Approach in Evaluating Stress-Strain Relationship in Torsional Test

다국어 초록 (Multilingual Abstract)

Determination of stress-strain relationship in torsional tests is complicated due to nonuniform stress-strain variation occurring
linearly with the radius in a soil specimen in torsion. The equivalent radius approach is adequate when calculating strain at low to
intermediate strains, however, the approach is less accurate when performing the test at higher strain levels. The modified equivalent
radius approach was developed to account for the problem more precisely. This approach was extended to generate the plots
of equivalent radius ratio versus strain using modified hyperbolic and Ramberg-Osgood models. Results showed the effects of soil
nonlinearity on the equivalent radius ratio curves were observed. Curve fitting was also performed to find the stress-strain relationship
by fitting the theoretical torque-rotation relationship to measured torque-rotation relationship.

다국어 초록 (Multilingual Abstract)

Determination of stress-strain relationship in torsional tests is complicated due to nonuniform stress-strain variation occurring
linearly with the radius in a soil specimen in torsion. The equivalent radius approach is adequate when calculating strain at low to
intermediate strains, however, the approach is less accurate when performing the test at higher strain levels. The modified equivalent
radius approach was developed to account for the problem more precisely. This approach was extended to generate the plots
of equivalent radius ratio versus strain using modified hyperbolic and Ramberg-Osgood models. Results showed the effects of soil
nonlinearity on the equivalent radius ratio curves were observed. Curve fitting was also performed to find the stress-strain relationship
by fitting the theoretical torque-rotation relationship to measured torque-rotation relationship.

참고문헌 (Reference)

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