• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.1
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• pp.83-94
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• 1994

The first part of this study dealt with the determination of soil parameters for Lade's double work-hardening model using the raw data obtained from cubical and cylinderal triaxial tests At present, it should be investigated which test can simulated satisfactorily the behavior of soft clayey foundation. In this regard, plate bearing test on the 2-dimentional model foundation(218cm long, 40cm wide, 19&m high) was performed, and finite element analysis carried out to abtain the behavior of the foundation. Settlement, lateral displacement, displacement vector and mode of failure were measured and these values were compared with numerical values in order to validate the numerical program developed by authors. The FEM technique was based on Christain-Boehmer's method, in which the displacement is obtained at each nodal point while stress and pore water pressure at each element.In this research, Biot's equation, which explains was elahorately the phisical meaning of consolidation, was selected, as a governing equation, coupled with Lade's double surface work-hardening constitutive model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.3
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• pp.107-113
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• 1990

A series of cubical triaxial tests with independent control of the three principal stresses were performed on a compressible sand. All specimens which were formed by depositing the fine sand loosely, were used. It was found that slope of the stress-strain curve increased with increased b value, and the major principal strain at failure first remains approximetely constant for b values smaller than about 0.3 for drained condition and 0.6 for undrained condition respectively, and thereafter decreases with increasing value of b. The test results showed that the direction of the strain increments at failure form acute angles with the failure surfaces for both the drained and undrained condition. The results are thus not in agreement with the normality criterion from classic plasticity theory. However, it was found that the projections of the plastic strain increment vectors on the octahedral plane are perpendicular to the faiure surface in that plane.

• Geotechnical Engineering
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• v.6 no.3
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• pp.65-76
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• 1990

A series of consolidated drained and untrained cubical triaxial tests were performed to investigate three dimensional strength characteristics of compressible sand. All specimens, which are formed by deposisting a fine sand loosely, were used. Failure strength in terms of effective stress analysis was greatly influenced by the variation of intermediate principal stress and so was failure criterion The adjusted effective frictional angles obtained by the stress state projected on the same octahedral plane showed almost same value, while the measured effective frictional angles showed considerable difference depending on the drainage conditions. Results of total stress analysis in undrained test turned out to fit Tresca's failure criterion well, but results of effective stress analysis turned out to fit Lade's failure criterion well.