• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.2
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• pp.148-158
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• 1998

The aims of this study are to evaluate the application on the stress-strain behavior of granite Soil using Lade's double work hardening constitutive model based on the theories of elasticity and plasticity. From two different sites of construction work, two disturbed and compacted weathered granite samples which are different in partical size and degree of weathering respectively were obtained. The specimen employed were sampled at Iksan and Pochon in order to predict the constitutive model. Using the computer program based on the regression analysis, 11 soil parameters for the model were determined from the simple tests such as an isotropic compression-expansion test and a series of drained conventional triaxial tests. In conclusion, it is shown that Lade's double work hardening model gives the good applicability for processing of stress-strain, work-hardening, work-softening and soil dilatancy. Therefore, this model in its present form is applicable to the compacted decomposed granite soil.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.3
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• pp.97-106
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• 2000

The study is closely relevant to Lade's single work hardening model. This model has been shown to have good applicability to cohesive soils. However the validation of this model on the clayey soils has not been satisfactorily reported. To scrutinize the applicability of this model on clayey foundation the laboratory tests for Kwangyang clayey soils were performed using the improved cubical triaxial test apparatus designed originally by Lade. A computer program was developed by which soil parameters for the single work-hardening model can be rationally determined by deleting some dispersed test data generated usually at the initial stage of laboratory tests. And using the program numerical analysis of the cubical clayey specimens using intermediate principal stress was carried out and a good agreement between observed values and numerical results was found.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.2
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• pp.133-144
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• 1996

To get accurate results, the realistic stress-strain relationships of soils are dependent on a number of factors such as soil types, density, stress levels and stress path. Such attempts are continuously being made by the developement of analytical models for soils incorporating all such factors. Isotropic compression-expansion test and a series of drained conventional triaxial tests with several stress path for Baekma river sand were performed to investigate parameters characteristics of Lade's single work hardening model dependant on the stress path. Using the computer program based on the regression analysis, the values of parameters for the model were determined. In conclusion, the parameters of Lade's model are little influenced by the stress paths. Though yield criterion parameters ( h, ${\alpha}$a) are much influenced by stress level and stress path, the parameters don't have influence on stress-strain behavior.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.1
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• pp.106-117
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• 1998

The nature of stress-path dependency, the principle that governs deformations in granular soil, and the use of Lade's double work-hardening model for predicting soil response for a variety of stress-paths have been investigated, and are examined The test results and the analyses presented show that under some conditions granular soils exhibit stress-path dependent behavior. For stress-paths involving unloading or reloading, the stress-path with the higher average stress level produces the larger strains, whereas all stress-paths having the same intial states of stress, and involving only primary loading conditions, produce strains of similar magnitudes. Experimental evidence indicates that the stress- path dependent response obtained from the double work-hardening model is also observed for real soils. It is concluded that the influence of stress history on the friction angle is negligible and the strains increment direction is uniquely determined from the state of stress but is not perpendicular to the yield surface. The strains calculated from Lade's double work-hardening model are in reasonable agreement with those measured.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.2
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• pp.191-203
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• 1992

This paper dealt with the statistical values including mean, standard deviation, variance and coefficient of variation for 14 soil parameters available of Lade's double work-hardening model in order to predict the behaviour of granular soil. 27 sets of all 14 parameters for Baekma river sand were determined by regression using raw data acquired from 12 isotropic compression tests and 9 triaxial compression tests with the variation of confining pressure of 1, 2, and $4kg/cm^2$ respectively 3 times performed during this study. The characteristics of each parameters were investigated. By determining the range of the upper and lower bound dependent on the increase and decrease of the standard deviation from mean value of parameters, sensitivity of all the parameters was scrutinized, by which in turn the influence of experimental error generated inevitably during tests on the determination of soil parameters was also examined.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.6
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• pp.95-103
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• 1998

Solutions of geotechnical engineering problems require calculation of deformation and stresses during various stages of loading. Powerful numerical methods are available to make such calculation even for complicated problems. To get accurate results, realistic stress-strain relationships of soil are dependent on a number of factors such as soil type, density, stress level and stress path. Attempts are continuously being made to develope analytical models for soils incorporating all such factors. The nature of stress-path dependency, the principle that governs deformations in sand, and the use of Lade's single work-hardening model for predicting sand response for a variety of stress-paths have been investigated and are examined. The test results and the analyses presented show that under some conditions sand exhibits stress-path dependent behavior. The strains calculated from Lade's single work-hardening model are in reasonable agreement with those measured, but some discrepancies occur. The largest difference between measured and calculated strains occurs for proportional loading with increasing stresses and for stress-path directions.

• Journal of Navigation and Port Research
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• v.36 no.5
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• pp.395-400
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• 2012

The stress-strain relationship of soil is dependent on a number of factors such as soil type, density, stress level and stress path. Th accurate stress-stain relationship can be predict using a constitutive model incorporated all influencing factors. In this study, an isotropic compression-expansion test and a series of drained conventional triaxial tests with several stress paths were performed on Baekma river sand to investigate parameters characteristics of Lade's single work hardening model depending on the stress path.. Based on test results, the parameters of yield function (h, ${\alpha}$) are not much influenced by stress level and stress path, the these parameters do affect a little bit of stress-strain behavior. The parameters h and ${\alpha}$ are closely related to failure criterion ${\eta}_1$, they can be replaced by failure criterion parament. We also observed that predicted values from the Lade's single hardening constitutive model are well matched with the observed data.

• 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.

• Journal of the Korean Geosynthetics Society
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• v.12 no.3
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• pp.55-64
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• 2013

In this study, a series of the isotropic compression-expansion tests and the Undrained triaxial tests were performed on low-plastic silt of Pocheon stone sludge. Using the tests results the characteristic of the parameters of Lade's single hardening constitutive model were investigated. We also observed that predicted values from the Lade's single hardening constitutive model were well consistent with the observed data. In experimental results the deviator stress showed the work hardening behaviour after reaching its yield stress. Therefore practically useful failure criterion for low-plastic silt were required. The stress-strain behavior predicted by 11 soil parameters are compared with the results obtained 9 parameters by correlation between h and ${\eta}_1$ and constant ${\alpha}$. They are poor matched each other.

• Geotechnical Engineering
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• v.10 no.1
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• pp.103-118
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• 1994

A series of drained triaxial testis was performed on a Band by use of cubical triaxial apparatus, in which three principal stresses could be applied independently. The stress -strain behavior on the same stress path with cubical triaxial test was analyzed with application of the isotropic single hardening constitutive model presented by Lade. The behavior predicted by the constitutive model presented good coincidence with experimental results during poi mary loading. However, the predicted Mo윤ding and reloading behavior wan much different from results of cubical triaxial testy. That is, the softening part of the prediction might result in a rough approximation, since the plastic work parameters of single hardening model were based on the hardening portion of the data.