Numerical analysis has become the important tool to assist geotechnical engineering project or case. Some of soil model are provided in numerical software. Hardening Soil model is advance soil model which become more widely used. Selecting the reliable parameter is a key to perform numerical simulation, thus laboratory testing such as triaxial test and oedometer test are applied to investigate the soil stiffness parameter. In addition to triaxial test and oedometer test, developing a reliable reconstitution soil method is a key to produce reliable soil sample.
Designing and performing reconstituted soil test is the first step to obtain reliable soil sample prior to triaxial test, oedometer test and bender element test. Based on the water content test, the new design of consolidometer (reconstituted soil) to produce undisturbed soil is quite reliable. A series of triaxial tests such as CK0U_AC, CIU_AC, CIU_AD, CK0U_AE, CIU_AE and oedometer test were conducted to evaluate the stiffness parameter such as initial Young’s Modulus (E0), secant Young’s Modulus (E50), oedometer Young’s Modulus (E50), and initial Shear Modulus (G0).
Finally, In order to verify the testing results, this study performed numerical simulation which is included back analysis of stress strain curve and parametric study of initial shear modulus (G0) and shear strain (?0.7). Based on parametric study, it can be concluded that the influence of shear strain ?0.7 is less significantly for extension test (CK0U_AE and CIU_AE) and initial shear modulus G0 for both of compression test and extension test did not influence significantly the stress strain curve.

Numerical analysis has become the important tool to assist geotechnical engineering project or case. Some of soil model are provided in numerical software. Hardening Soil model is advance soil model which become more widely used. Selecting the reliable parameter is a key to perform numerical simulation, thus laboratory testing such as triaxial test and oedometer test are applied to investigate the soil stiffness parameter. In addition to triaxial test and oedometer test, developing a reliable reconstitution soil method is a key to produce reliable soil sample.
Designing and performing reconstituted soil test is the first step to obtain reliable soil sample prior to triaxial test, oedometer test and bender element test. Based on the water content test, the new design of consolidometer (reconstituted soil) to produce undisturbed soil is quite reliable. A series of triaxial tests such as CK0U_AC, CIU_AC, CIU_AD, CK0U_AE, CIU_AE and oedometer test were conducted to evaluate the stiffness parameter such as initial Young’s Modulus (E0), secant Young’s Modulus (E50), oedometer Young’s Modulus (E50), and initial Shear Modulus (G0).
Finally, In order to verify the testing results, this study performed numerical simulation which is included back analysis of stress strain curve and parametric study of initial shear modulus (G0) and shear strain (?0.7). Based on parametric study, it can be concluded that the influence of shear strain ?0.7 is less significantly for extension test (CK0U_AE and CIU_AE) and initial shear modulus G0 for both of compression test and extension test did not influence significantly the stress strain curve.

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