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Effect of Tunnelling on Settlement of a Building: A Numerical Approach

Year 2025, Volume: 6 Issue: 1, 124 - 139, 30.06.2025
https://doi.org/10.53501/rteufemud.1550652

Abstract

Land shortages due to population growth and the sustainable development of cities have necessitated the use of underground systems. Although tunnels, which mostly provide solutions to transport problems, are frequently used today, the construction of tunnels in large cities poses significant issues. Regardless of the construction method, deformations are inevitable during tunnelling. Tunnelling machines apply pressure to the surfaces during the excavation of the tunnel surface. However, during construction, the pressures are not adjusted correctly, and deformations are observed in the ground. Since these deformations may cause major damage to the surrounding structures when they reach the ground surface, it should be calculated how much deformation may occur before construction, and necessary precautions should be taken. Therefore, this study aims to define the deformations that will occur on the soil surface. In this context, numerical analyses were performed. During the numerical studies, Plaxis 2D based on finite element method (FEM), was used to create the tunnel modelling in the clayey soil. A tunnel boring machine (TBM) was used during tunnelling in the modelling. The excavation diameter of the tunnel, cover thickness, foundation width and epicentre distance from the tunnel axis to the structure foundation were analysed in the geometric model. The effects of the geometrical parameters of the tunnel, the building and the clay soil on the displacements were determined numerically. As a result, it was determined that tunnel depth, tunnel diameter, cover thickness and foundation width are effective parameters for settlement of buildings constructed on clay soils.

References

  • Ads, A., Islam M.S., Iskander, M. (2023). Longitudinal settlements during tunneling in soft Clay, using transparent soil models. Tunnelling and Underground Space Technology, vol. 136. https://doi.org/10.1016/j.tust.2023.105042
  • Atkinson, J.H., Potts, D.M. (1977). Stability of a shallow circular tunnel in cohesionless soil. Geotechnique, 27(2), 203–215. https://doi.org/10.1680/geot.1977.27.2.203
  • Attewell, P.B., Woodman, J.P. (1982). Predicting the dynamics of ground settlement and its derivatives caused by tunnelling in soil. Ground Engineering, 15(8), 13–22, 1982.
  • Celestino, T.B., Gomes, R.A.M.P., Bortolucci, A.A. (2000). Errors in ground distortions due to settlement trough adjustment. Tunneling and Underground Space Technology, 15(1), 97–100. https://doi.org/10.1016/S0886-7798(99)00054-1
  • Chen, R.P., Zhang, P., Kang, X., Zhong, Z.Q., Liu, Y., Wu, H.N. (2019). Prediction of maximum surface settlement caused by earth pressure balance (EPB) shield tunneling with ANN methods. Soils and Foundations, 59(2), 284–295. https://doi.org/10.1016/j.sandf.2018.11.005
  • Cheng, H.Z., Chen, J., Chen, G.L. (2019). Analysis of ground surface settlement induced by a large EPB shield tunnelling: A case study in Beijing, China. Environmental Earth Sciences, 78(20), 605. https://doi.org/10 .1007/s12665-019-8620-6
  • Du, D., Dias, D., Do, N. (2020). Effect of surcharge loading on horseshoe-shaped tunnels excavated in saturated soft rocks. Journal of Rock Mechanics and Geotechnical Engineering, 12(6), 1339–1346. https://doi.org/10.1016/j.jrmge.2020.08.001
  • Hellawell, E.E., Hawley, A.J., Pooley, S.D., Garrod, B., Legett, M. (2001). Metros under construction around the world, Proceedings of the institution of civil engineers: Geotechnical Engineering, 149, 29–39. https://doi.org/10.1680/geng.2001.149.1.29
  • Huang, Z., Zhang, H., Fu, H., Ma, S., Liu, Y. (2020). Deformation response induced by surcharge loading above shallow shield tunnels in soft soil. KSCE Journal of Civil Engineering, 24 (8), 2533–2545. https://doi.org/10.1007/s12205-020-0404-8
  • İdeCAD Statik. (2018). İdeYAPI, Turkey.
  • Li, S.C., Wang. M.B. (2008). Elastic analysis of stress–displacement field for a lined circular tunnel at great depth due to ground loads and internal pressure. Tunnelling and Underground Space Technology, 23(6), 609–617. https://doi.org/10.1016/j.tust.2007.11.004
  • Mair, R.J., Taylor, R.N., Bracegirdle, A. (1993). Subsurface settlement profiles above tunnels in clays. Géotechnique, 43(2), 315–320. https://doi.org/10.1680/geot.1993.43.2.315
  • Mair, R.J., Taylor, R.N. (1997). Bored tunnelling in the urban environment. In 1997 Proceedings of the fourteenth international conference on soil mechanic sand foundation engineering, Rotterdam, pp. 2353-2385, September.
  • Marshall, A.M., Farrell, R., Klar, A., Mair, R. (2012). Tunnels in sands: the effect of size, depth and volume loss on greenfield displacements. G´eotechnique, 62(5), 385–399. https://doi.org/10.1680/geot.10.P.047
  • Moghaddasi, M.R., Noorian-Bidgoli, M. (2018). ICA-ANN, ANN and multiple regression models for prediction of surface settlement caused by tunneling. Tunneling and Underground Space Technology, 79, 197–209. https://doi.org/10.1016/j.tust.2018.04.016
  • Namli, M., Aras, F. (2020). Investigation of effects of dynamic loads in metro tunnels during construction and operation on existing buildings. Arabian Journal of Geosciences, 13, 424. https://doi.org/10.1007/s12517-020-05456-x
  • O’Reilly, M.P., New, B.M. (1982). Settlements above tunnels in the United Kindom–Their magnitudes and prediction. 3th international symposium by Institution of Mining and Metallurgy, 31 January, London, England.
  • Peck, R.B. (1969). Deep excavation sand tunneling in soft ground. Proceedings of the 7th International Conference on Soil Mechanics and Foundation Engineering, 25 August, Mexico City, Mexico.
  • Plaxis 2D. (2010). Plaxis 2D Material Models Manual. Version 8.6, Netherlands.
  • Polshin, D.E., Tokar, R.A. (1957). Maximum allowable non-uniform settlement of structures, Proceedings of the 4th International Conference on Soil Mechanics and Foundation Engineering, 12-24 August, London, England.
  • Pourtaghi, A., Lotfollahi-Yaghin, M.A. (2012) Wavenet ability assessment in comparison to ANN for predicting the maximum surface settlement caused by tunneling. Tunneling and Underground Space Technology, 28(1), 257–271. https://doi.org/10.1016/j.tust.2011.11.008
  • Rankin, W.J. (1988). Ground movements resulting from urban tunnelling: predictions and effects. Geological Society, London, Engineering Geology Special Publications, 5(1), 79–92. https://doi:10.1144/gsl.eng.1988.005.01.06
  • Shen, S.-L., Elbaz, K., Shaban, W. M., Zhou, A. (2022). Real-time prediction of shield moving trajectory during tunnelling. Acta Geotechnica, 17(4), 1533–1549. https://doi:10.1007/s11440-022-01461-4
  • Skempton, A.W., Macdonald, D.H. (1956). The allowable settlements of buildings. Proceedings of the Institution of Civil Engineers, 5(6), 727-768. https://doi.org/10.1680/ipeds.1956.12202
  • Verruijt, A., Booker, J. R. (1996). Surface settlements due to deformation of a tunnel in an elastic half plane. Géotechnique, 46, 753–756. https://doi:10.1680/geot. 1996.46.4.753
  • Vorster, T.E.B., Klar, A., Soga, K., Mair, R.J. (2005). Estimating the effects of tunneling on existing pipelines. Journal of Geotechnical and Geoenvironmental, 131(11), 1399–1410. https://doi.org/10.1061/(ASCE)1090-0241(2005)131:11(1399)
  • Wang, H.N., Chen, X.P., Jiang, M.J., Song, F., Wu, L. (2018a). The analytical predictions on displacement and stress around shallow tunnels subjected to surcharge loadings. Tunnelling and Underground Space Technology, 71, 403–427. https://doi.org/10.1016/j.tust.2017.09.015
  • Wang, H.N., Wu, L., Jiang, M.J., Song, F. (2018b). Analytical stress and displacement due to twin tunneling in an elastic semi-infinite ground subjected to surcharge loads. International Journal for Numerical and Analytical Methods in Geomechanics, 42(6), 809–828. https://doi.org/10.1002/nag.2764
  • Wilun, Z., Starzewski, K. (1972). Soil Mechanics in Foundation Engineering, 2. Theory and Practice. Intertext, London.
  • Wu, H.-N., Shen, S.-L., Yang, J., Zhou, A. (2018). Soil-tunnel interaction modelling for shield tunnels considering shearing dislocation in longitudinal joints. Tunnelling and Underground Space Technology, 78, 168–177. https://doi:10.1016/j.tust.2018.04.009
  • Yamamoto, K., Lyamin, A.V., Wilson, D.W., Sloan, S. W., Abbo, A.J. (2011). Stability of a single tunnel in cohesive–frictional soil subjected to surcharge loading. Canadian Geotechnical Journal, 48(12), 1841-1854. https://doi.org/10.1139/t11-078
  • Yamamoto, K., Lyamin, A.V., Wilson, D.W., Sloan, S.W., Abbo, A.J. (2012). Stability of dual circular tunnels in cohesive-frictional soil subjected to surcharge loading. Computers and Geotechnics, 50, 41–54. https://doi.org/10.1016/j.compgeo.2012.12.008
  • Yamamoto, K., Lyamin, A.V., Wilson, D.W., Sloan, S. W., Abbo, A.J. (2014). Stability of dual square tunnels in cohesive-frictional soil subjected to surcharge loading. Canadian Geotechnical Journal, 51(8), 829-843. https://doi.org/10.1139/cgj-2013-0481
  • Yan, T., Shen, S.-L., Zhou, A., Lyu, H.-M. (2021). Construction efficiency of shield tunnelling through soft deposit in Tianjin, China. Tunnelling and Underground Space Technology, 112, 103917. https://doi.org/10.1016/j.tust.2021.103917
  • Yang, F., Zheng, X.C., Zhang, J., Yang. J.S. (2017). Upper bound analysis of stability of dual circular tunnels subjected to surcharge loading in cohesive-frictional soils. Tunnelling and Underground Space Technology, 61, 150–160. https://doi.org/10.1016/j.tust.2016.10.006
  • Zhang, P., Yin, Z.-Y., Chen, R.P. (2020). Analytical and semi-analytical solutions for describing tunneling-induced transverse and longitudinal settlement troughs. International Journal of Geomechanics, 20(8), 04020126. https://doi.org/10.1061/(asce)gm.1943-5622.0001748
  • Zhai, W.Z., Chapman, D., Zhang, D.M., Huang, H.W. (2020). Experimental study on the effectiveness of strengthening over-deformed segmental tunnel lining by steel plates. Tunnelling and Underground Space Technology, 104, 103530. https://doi.org/10.1016/j.tust.2020.103530
  • Zhang, M.G., Zhou, S.H., Huang, D.W., Wang, X.Z., - Liu, H.B. (2016). Analysis of influence of surface surcharge on subway shield tunnel. Rock and Soil Mechanics, 37(8), 2271–2278.
  • Zhang, Z.X., Liu, C., Huang, X. (2017). Numerical analysis of volume loss caused by tunnel face instability in soft soils. Environmental Earth Sciences, 76, 1–19. https://doi:10.1007/s12665-017-6893-1
  • Zhou, J., Sh, X., Du, K., Qiu, X., Li, X., Mitri, H.S. (2017). Feasibility of random-forest approach for prediction of ground settlements induced by the construction of a shield-driven tunnel. International Journal of Geomechanics, 17(6), 04016129. https://doi:10.1061/(ASCE)GM.1943-5622.0000817

Tünel Açmanın Bir Binanın Oturmasına Etkisi: Sayısal Bir Yaklaşım

Year 2025, Volume: 6 Issue: 1, 124 - 139, 30.06.2025
https://doi.org/10.53501/rteufemud.1550652

Abstract

Nüfus artışına bağlı olarak yaşanan arazi sıkıntısı ve şehirlerin sürdürülebilir gelişimi, yeraltı ulaşım sistemlerinin kullanımını zorunlu hale getirmiştir. Çoğunlukla ulaşım sorunlarına çözüm sağlayan tüneller, günümüzde sıklıkla kullanılsa da büyük şehirlerde tünel yapımı önemli sorunlar teşkil etmektedir. Yapım yöntemi ne olursa olsun, tünel açma sırasında zeminde deformasyonlar kaçınılmazdır. Tünel açma makineleri, tünel yüzeyinin kazılması sırasında yüzeylere basınç uygular. Ancak inşaat aşamasında bu basınçlar doğru ayarlanmamakta ve zeminde deformasyonlar gözlenmektedir. Bu deformasyonlar zemin yüzeyine ulaştığında çevredeki yapılara büyük zararlar verebileceğinden, inşaat öncesinde ne kadar deformasyon oluşabileceği hesaplanmalı ve gerekli önlemler alınmalıdır. Bu nedenle bu çalışmada zemin yüzeyindeki yapı temelinde oluşacak deformasyonların belirlenmesi amaçlanmıştır. Bu kapsamda sayısal analizler gerçekleştirilmiştir. Sayısal çalışmalar sırasında, killi zeminde tünel modellemesini oluşturmak için sonlu elemanlar yöntemine dayalı Plaxis 2D programı kullanılmıştır. Modellemede tünel açma sırasında bir tünel açma makinesi (TBM) kullanılmıştır. Geometrik modelde tünelin kazı çapı, örtü kalınlığı, temel genişliği ve tünel ekseninden yapı temeline olan episantrik mesafe analiz edilmiştir. Tünelin, yapının ve zeminin geometrik parametrelerinin yer değiştirmeler üzerindeki etkileri sayısal olarak belirlenmiştir. Sonuç olarak, tünel derinliği, tünel çapı, örtü kalınlığı ve temel genişliğinin killi zeminler üzerine inşa edilen binanın oturması üzerinde etkili parametreler olduğu tespit edilmiştir.

References

  • Ads, A., Islam M.S., Iskander, M. (2023). Longitudinal settlements during tunneling in soft Clay, using transparent soil models. Tunnelling and Underground Space Technology, vol. 136. https://doi.org/10.1016/j.tust.2023.105042
  • Atkinson, J.H., Potts, D.M. (1977). Stability of a shallow circular tunnel in cohesionless soil. Geotechnique, 27(2), 203–215. https://doi.org/10.1680/geot.1977.27.2.203
  • Attewell, P.B., Woodman, J.P. (1982). Predicting the dynamics of ground settlement and its derivatives caused by tunnelling in soil. Ground Engineering, 15(8), 13–22, 1982.
  • Celestino, T.B., Gomes, R.A.M.P., Bortolucci, A.A. (2000). Errors in ground distortions due to settlement trough adjustment. Tunneling and Underground Space Technology, 15(1), 97–100. https://doi.org/10.1016/S0886-7798(99)00054-1
  • Chen, R.P., Zhang, P., Kang, X., Zhong, Z.Q., Liu, Y., Wu, H.N. (2019). Prediction of maximum surface settlement caused by earth pressure balance (EPB) shield tunneling with ANN methods. Soils and Foundations, 59(2), 284–295. https://doi.org/10.1016/j.sandf.2018.11.005
  • Cheng, H.Z., Chen, J., Chen, G.L. (2019). Analysis of ground surface settlement induced by a large EPB shield tunnelling: A case study in Beijing, China. Environmental Earth Sciences, 78(20), 605. https://doi.org/10 .1007/s12665-019-8620-6
  • Du, D., Dias, D., Do, N. (2020). Effect of surcharge loading on horseshoe-shaped tunnels excavated in saturated soft rocks. Journal of Rock Mechanics and Geotechnical Engineering, 12(6), 1339–1346. https://doi.org/10.1016/j.jrmge.2020.08.001
  • Hellawell, E.E., Hawley, A.J., Pooley, S.D., Garrod, B., Legett, M. (2001). Metros under construction around the world, Proceedings of the institution of civil engineers: Geotechnical Engineering, 149, 29–39. https://doi.org/10.1680/geng.2001.149.1.29
  • Huang, Z., Zhang, H., Fu, H., Ma, S., Liu, Y. (2020). Deformation response induced by surcharge loading above shallow shield tunnels in soft soil. KSCE Journal of Civil Engineering, 24 (8), 2533–2545. https://doi.org/10.1007/s12205-020-0404-8
  • İdeCAD Statik. (2018). İdeYAPI, Turkey.
  • Li, S.C., Wang. M.B. (2008). Elastic analysis of stress–displacement field for a lined circular tunnel at great depth due to ground loads and internal pressure. Tunnelling and Underground Space Technology, 23(6), 609–617. https://doi.org/10.1016/j.tust.2007.11.004
  • Mair, R.J., Taylor, R.N., Bracegirdle, A. (1993). Subsurface settlement profiles above tunnels in clays. Géotechnique, 43(2), 315–320. https://doi.org/10.1680/geot.1993.43.2.315
  • Mair, R.J., Taylor, R.N. (1997). Bored tunnelling in the urban environment. In 1997 Proceedings of the fourteenth international conference on soil mechanic sand foundation engineering, Rotterdam, pp. 2353-2385, September.
  • Marshall, A.M., Farrell, R., Klar, A., Mair, R. (2012). Tunnels in sands: the effect of size, depth and volume loss on greenfield displacements. G´eotechnique, 62(5), 385–399. https://doi.org/10.1680/geot.10.P.047
  • Moghaddasi, M.R., Noorian-Bidgoli, M. (2018). ICA-ANN, ANN and multiple regression models for prediction of surface settlement caused by tunneling. Tunneling and Underground Space Technology, 79, 197–209. https://doi.org/10.1016/j.tust.2018.04.016
  • Namli, M., Aras, F. (2020). Investigation of effects of dynamic loads in metro tunnels during construction and operation on existing buildings. Arabian Journal of Geosciences, 13, 424. https://doi.org/10.1007/s12517-020-05456-x
  • O’Reilly, M.P., New, B.M. (1982). Settlements above tunnels in the United Kindom–Their magnitudes and prediction. 3th international symposium by Institution of Mining and Metallurgy, 31 January, London, England.
  • Peck, R.B. (1969). Deep excavation sand tunneling in soft ground. Proceedings of the 7th International Conference on Soil Mechanics and Foundation Engineering, 25 August, Mexico City, Mexico.
  • Plaxis 2D. (2010). Plaxis 2D Material Models Manual. Version 8.6, Netherlands.
  • Polshin, D.E., Tokar, R.A. (1957). Maximum allowable non-uniform settlement of structures, Proceedings of the 4th International Conference on Soil Mechanics and Foundation Engineering, 12-24 August, London, England.
  • Pourtaghi, A., Lotfollahi-Yaghin, M.A. (2012) Wavenet ability assessment in comparison to ANN for predicting the maximum surface settlement caused by tunneling. Tunneling and Underground Space Technology, 28(1), 257–271. https://doi.org/10.1016/j.tust.2011.11.008
  • Rankin, W.J. (1988). Ground movements resulting from urban tunnelling: predictions and effects. Geological Society, London, Engineering Geology Special Publications, 5(1), 79–92. https://doi:10.1144/gsl.eng.1988.005.01.06
  • Shen, S.-L., Elbaz, K., Shaban, W. M., Zhou, A. (2022). Real-time prediction of shield moving trajectory during tunnelling. Acta Geotechnica, 17(4), 1533–1549. https://doi:10.1007/s11440-022-01461-4
  • Skempton, A.W., Macdonald, D.H. (1956). The allowable settlements of buildings. Proceedings of the Institution of Civil Engineers, 5(6), 727-768. https://doi.org/10.1680/ipeds.1956.12202
  • Verruijt, A., Booker, J. R. (1996). Surface settlements due to deformation of a tunnel in an elastic half plane. Géotechnique, 46, 753–756. https://doi:10.1680/geot. 1996.46.4.753
  • Vorster, T.E.B., Klar, A., Soga, K., Mair, R.J. (2005). Estimating the effects of tunneling on existing pipelines. Journal of Geotechnical and Geoenvironmental, 131(11), 1399–1410. https://doi.org/10.1061/(ASCE)1090-0241(2005)131:11(1399)
  • Wang, H.N., Chen, X.P., Jiang, M.J., Song, F., Wu, L. (2018a). The analytical predictions on displacement and stress around shallow tunnels subjected to surcharge loadings. Tunnelling and Underground Space Technology, 71, 403–427. https://doi.org/10.1016/j.tust.2017.09.015
  • Wang, H.N., Wu, L., Jiang, M.J., Song, F. (2018b). Analytical stress and displacement due to twin tunneling in an elastic semi-infinite ground subjected to surcharge loads. International Journal for Numerical and Analytical Methods in Geomechanics, 42(6), 809–828. https://doi.org/10.1002/nag.2764
  • Wilun, Z., Starzewski, K. (1972). Soil Mechanics in Foundation Engineering, 2. Theory and Practice. Intertext, London.
  • Wu, H.-N., Shen, S.-L., Yang, J., Zhou, A. (2018). Soil-tunnel interaction modelling for shield tunnels considering shearing dislocation in longitudinal joints. Tunnelling and Underground Space Technology, 78, 168–177. https://doi:10.1016/j.tust.2018.04.009
  • Yamamoto, K., Lyamin, A.V., Wilson, D.W., Sloan, S. W., Abbo, A.J. (2011). Stability of a single tunnel in cohesive–frictional soil subjected to surcharge loading. Canadian Geotechnical Journal, 48(12), 1841-1854. https://doi.org/10.1139/t11-078
  • Yamamoto, K., Lyamin, A.V., Wilson, D.W., Sloan, S.W., Abbo, A.J. (2012). Stability of dual circular tunnels in cohesive-frictional soil subjected to surcharge loading. Computers and Geotechnics, 50, 41–54. https://doi.org/10.1016/j.compgeo.2012.12.008
  • Yamamoto, K., Lyamin, A.V., Wilson, D.W., Sloan, S. W., Abbo, A.J. (2014). Stability of dual square tunnels in cohesive-frictional soil subjected to surcharge loading. Canadian Geotechnical Journal, 51(8), 829-843. https://doi.org/10.1139/cgj-2013-0481
  • Yan, T., Shen, S.-L., Zhou, A., Lyu, H.-M. (2021). Construction efficiency of shield tunnelling through soft deposit in Tianjin, China. Tunnelling and Underground Space Technology, 112, 103917. https://doi.org/10.1016/j.tust.2021.103917
  • Yang, F., Zheng, X.C., Zhang, J., Yang. J.S. (2017). Upper bound analysis of stability of dual circular tunnels subjected to surcharge loading in cohesive-frictional soils. Tunnelling and Underground Space Technology, 61, 150–160. https://doi.org/10.1016/j.tust.2016.10.006
  • Zhang, P., Yin, Z.-Y., Chen, R.P. (2020). Analytical and semi-analytical solutions for describing tunneling-induced transverse and longitudinal settlement troughs. International Journal of Geomechanics, 20(8), 04020126. https://doi.org/10.1061/(asce)gm.1943-5622.0001748
  • Zhai, W.Z., Chapman, D., Zhang, D.M., Huang, H.W. (2020). Experimental study on the effectiveness of strengthening over-deformed segmental tunnel lining by steel plates. Tunnelling and Underground Space Technology, 104, 103530. https://doi.org/10.1016/j.tust.2020.103530
  • Zhang, M.G., Zhou, S.H., Huang, D.W., Wang, X.Z., - Liu, H.B. (2016). Analysis of influence of surface surcharge on subway shield tunnel. Rock and Soil Mechanics, 37(8), 2271–2278.
  • Zhang, Z.X., Liu, C., Huang, X. (2017). Numerical analysis of volume loss caused by tunnel face instability in soft soils. Environmental Earth Sciences, 76, 1–19. https://doi:10.1007/s12665-017-6893-1
  • Zhou, J., Sh, X., Du, K., Qiu, X., Li, X., Mitri, H.S. (2017). Feasibility of random-forest approach for prediction of ground settlements induced by the construction of a shield-driven tunnel. International Journal of Geomechanics, 17(6), 04016129. https://doi:10.1061/(ASCE)GM.1943-5622.0000817
There are 40 citations in total.

Details

Primary Language English
Subjects Civil Geotechnical Engineering, Numerical Modelization in Civil Engineering, Soil Mechanics in Civil Engineering
Journal Section Research Articles
Authors

Bayram Ateş 0000-0002-1251-7053

Erol Şadoğlu 0000-0003-3757-5126

Publication Date June 30, 2025
Submission Date September 16, 2024
Acceptance Date December 1, 2024
Published in Issue Year 2025 Volume: 6 Issue: 1

Cite

APA Ateş, B., & Şadoğlu, E. (2025). Effect of Tunnelling on Settlement of a Building: A Numerical Approach. Recep Tayyip Erdogan University Journal of Science and Engineering, 6(1), 124-139. https://doi.org/10.53501/rteufemud.1550652

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