Tünel Kazısından Dolayı Zemin Yüzeyindeki Oturmaların Mohr- Coulomb ve Pekleşen Zemin Modelleriyle Nümerik Tahminlerinin Karşılaştırılması

Zemin içinde yapılan tünel kazısı nedeniyle, zemindeki gerilmeler boşalarak kazı alanında elastik ve plastik

Anahtar Kelimeler:

Sonlu elemanlar metodu, malzeme modelleri, plaxıs, yüzey oturması, tünel

Comparison of Mohr-Coulomb and Hardening Soil Models’ Numerical Estimation of Ground Surface Settlement Caused by Tunneling

Due to in depth tunnel excavation, tensions in the soil are eased, causing elastic and plasticdeformations in the area of tunnel and leading to surface settlement at the ground level. Currently, along withthe use of numerical methods in analysis and design of engineering projects, it is known that this method hasused extensively in the analysis of problems related to geotechnical engineering and tunneling. Selection of theappropriate parameters and soil model can have a significant impact on the results of numerical analysis. TheMohr-Coulomb elastic-plastic model (MC) is one of the most widely used models, used in cases evaluating thehardness of materials, independent of the surface tension. If the Mohr-Coulomb used for numerical modelingof tunnel where in-depth tunneling excavation is involved and where an increase in maximum ground surfacesettlement and decrease in the reliability of stability of tunnels can be seen, which may not be appropriate in someconditions. The more appropriate model should be used to solve this problem, one that can model the hardness ofmaterials based on changes in the level of stress. In this study, the maximum ground surface settlement due to tunnelexcavation, obtained from Mohr- Coulomb model was compared with those of Hardening Soil (HS) Model results.Therefore, the ground surface settlement because of an assumption tunnel in different depths was analyzed withMohr-Coulomb and Hardening Soil models by using PLAXIS 2D. As a result of the analyzes, it is observed that asthe depth of the tunnel increases, the settlements on the ground surface decrease according to Mohr-Coulomb andapproach the real values.

Keywords:

Finite element method, material models, plaxis, surface settlement, tunneling,

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