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## entrConstitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental VerificationConstitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification

### Foundations constitute a significant part of the design of civil engineering systems. Geotechnical considerations are particularly important in identifying the conditions leading to instability of shallow and deep foundations under various loadings. In the case the foundation layer is clay, one should identify the conditions leading to failure of clay soil upon loading. The most common way of doing so is to theorize the constitutive behavior of the soil using mathematical equations. In this study, constitutive modeling of clays under monotonic loadings is presented using the Generalized Plasticity Theory. Numerical formulation is summarized in terms of governing equations which are solved for each load step by an explicit integration method which is implemented into a computer program. Elasto-plastic constitutive matrix is derived based upon the inversion of strain-stress relationship without using a yield or a potential function in the model which is used to get the stress-strain incremental relationship. Plastic strains are then calculated using a non-associative flow rule. Subsequently, a number of drained and undrained strain-controlled triaxial tests are simulated to verify the model and its implementation. Simulation results demonstrate the effectiveness and the capability of the model to capture static behavior of normally and overconsolidated clays.

Foundations constitute a significant part of the design of civil engineering systems. Geotechnical considerations are particularly important in identifying the conditions leading to instability of shallow and deep foundations under various loadings. In the case the foundation layer is clay, one should identify the conditions leading to failure of clay soil upon loading. The most common way of doing so is to theorize the constitutive behavior of the soil using mathematical equations. In this study, constitutive modeling of clays under monotonic loadings is presented using the Generalized Plasticity Theory. Numerical formulation is summarized in terms of governing equations which are solved for each load step by an explicit integration method which is implemented into a computer program. Elasto-plastic constitutive matrix is derived based upon the inversion of strain-stress relationship without using a yield or a potential function in the model which is used to get the stress-strain incremental relationship. Plastic strains are then calculated using a non-associative flow rule. Subsequently, a number of drained and undrained strain-controlled triaxial tests are simulated to verify the model and its implementation. The related tests are also simulated using the well-known modified Cam Clay model to highlight the capabilities of the Generalized Plasticity model. Simulation results demonstrate the effectiveness and the capability of the model to capture static behavior of normally and overconsolidated clays.
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Birincil Dil en Mühendislik Araştırma Makalesi Orcid: 0000-0001-7632-2303Yazar: Mehmet Barış Can ÜLKER (Sorumlu Yazar)Ülke: Turkey Yayımlanma Tarihi : 1 Haziran 2020
 Bibtex @araştırma makalesi { politeknik516345, journal = {Politeknik Dergisi}, issn = {}, eissn = {2147-9429}, address = {Gazi Üniversitesi Teknoloji Fakültesi 06500 Teknikokullar - ANKARA}, publisher = {Gazi Üniversitesi}, year = {2020}, volume = {23}, pages = {361 - 369}, doi = {10.2339/politeknik.516345}, title = {Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification}, key = {cite}, author = {ÜLKER, Mehmet Barış Can} } APA ÜLKER, M . (2020). Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification. Politeknik Dergisi , 23 (2) , 361-369 . DOI: 10.2339/politeknik.516345 MLA ÜLKER, M . "Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification". Politeknik Dergisi 23 (2020 ): 361-369 Chicago ÜLKER, M . "Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification". Politeknik Dergisi 23 (2020 ): 361-369 RIS TY - JOUR T1 - Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification AU - Mehmet Barış Can ÜLKER Y1 - 2020 PY - 2020 N1 - doi: 10.2339/politeknik.516345 DO - 10.2339/politeknik.516345 T2 - Politeknik Dergisi JF - Journal JO - JOR SP - 361 EP - 369 VL - 23 IS - 2 SN - -2147-9429 M3 - doi: 10.2339/politeknik.516345 UR - https://doi.org/10.2339/politeknik.516345 Y2 - 2019 ER - EndNote %0 Politeknik Dergisi Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification %A Mehmet Barış Can ÜLKER %T Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification %D 2020 %J Politeknik Dergisi %P -2147-9429 %V 23 %N 2 %R doi: 10.2339/politeknik.516345 %U 10.2339/politeknik.516345 ISNAD ÜLKER, Mehmet Barış Can . "Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification". Politeknik Dergisi 23 / 2 (Haziran 2020): 361-369 . https://doi.org/10.2339/politeknik.516345 AMA ÜLKER M . Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification. Politeknik Dergisi. 2020; 23(2): 361-369. Vancouver ÜLKER M . Constitutive Modeling of Monotonic Behavior of Clays: Mathematical Formulation, Numerical Implementation and Experimental Verification. Politeknik Dergisi. 2020; 23(2): 369-361.

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