3B Dinamik Yapı-Zemin Etkileşimi Modellemelerinde Ağ Tipinin Rolü

Öz

Yapı-zemin etkileşimi problemi sayısal modellemenin gelişmesiyle beraber son yıllarda birçok araştırmaya olanak sağlamaktadır. Bu problemin en önemli adımlarından biri zemin davranış analizleridir. ZDA yapının yokluğunda zeminin deprem yükleri altında göstereceği tepkileri anlamak ve yorumlamak için tasarımcıya önemli veriler sunmaktadır. Bu çalışmada ağ tipinin dinamik yapı zemin etkileşimi üzerindeki etkisi 3-boyutlu sonlu elemanlar yöntemi aracılığıyla ZDA üzerinden araştırılmaktadır. Çalışmada 3 farklı ağ tipi (hexahedral, tetrahedral ve hybrid) kullanılarak oluşturulan modellerin yanal sınırlarına geçirgen sınırlar yerleştirilmiştir. Geliştirilen 3-boyutlu modeller aynı deprem etkisi altında yapılan 1-boyutlu model sonuçlarıyla karşılaştırılarak doğrulanmıştır. Analizlerde, zeminin doğrusal elastik davranış sergilediği varsayılmış ve tüm 1B ve 3B analizler bu varsayım temelinde gerçekleştirilmiştir. 3B modeller, zemin yüzeyi tepki spektrumu aracılığıyla 1-boyutlu sonuçları başarılı bir biçimde temsil etmektedir. Çalışma, doğru bir şekilde yapılandırılmış bir ağ yapısı kullanıldığında, zemin sisteminin dinamik tepkisinin eleman tipinden büyük ölçüde bağımsız olduğunu ortaya koymaktadır. Buna karşılık, otomatik oluşturulmuş düzensiz ağ yapıları hatalı davranışa yol açabilmektedir. Değerlendirilen ağ tipleri arasında, hibrit ağlar hesaplama verimliliği açısından en uygun ağ tipi olduğu anlaşılmaktadır.

Anahtar Kelimeler

• Ağ tipi
• Sonlu elemanlar yöntemi
• Zemin davranış analizleri
• Yapı-zemin etkileşimi
• Dinamik analiz

ROLE OF MESH TYPE IN 3D DYNAMIC SOIL–STRUCTURE INTERACTION SIMULATIONS

Öz

With the advancement of numerical modeling techniques, the problem of soil–structure interaction (SSI) has become the subject of extensive research in recent years. One of the most critical stages of this problem is the site response analysis (SRA). SRA provides designers with valuable insights into the soil's expected seismic response in the superstructure's absence. The present work investigates the influence of mesh type on dynamic SSI through three-dimensional (3D) finite element-based SRA. Models were developed using three different mesh types—hexahedral, tetrahedral, and hybrid—with absorbing boundary conditions applied along the lateral edges. The 3D model results were verified by comparison with one-dimensional (1D) analyses subjected to the same ground motion. In the study, the soil was assumed to exhibit linear elastic behavior, and all 1D and 3D analyses were performed based on this assumption. The 3D models could accurately represent the 1D site response through ground surface response spectrum. The findings reveal that the dynamic response of the soil system is mainly independent of the element type provided that a properly structured and sufficiently refined mesh is employed. Conversely, auto-generated irregular meshes tend to produce inaccurate results. Among the mesh types evaluated, hybrid meshes offer the most favorable balance regarding computational efficiency.

Anahtar Kelimeler

• Mesh type
• Finite element method
• Site response analysis
• Soil-structure interaction
• Dynamic analysis

Kaynakça

1. Alsaleh, H., & Shahrour, I. (2009). Influence of plasticity on the seismic soil-micropiles-structure interaction. Soil Dynamics and Earthquake Engineering, 29(3), 574–578. doi:10.1016/j.soildyn.2008.04.008
2. Ashford, S. A., & Sitar, N. (2001). Effect of element size on the static finite element analysis of steep slopes. International Journal for Numerical and Analytical Methods in Geomechanics, 25(14), 1361–1376. Doi:10.1002/NAG.184
3. Bolisetti, C., Whittaker, A. S., & Coleman, J. L. (2018). Linear and nonlinear soil-structure interaction analysis of buildings and safety-related nuclear structures. Soil Dynamics and Earthquake Engineering, 107, 218–233. Doi:10.1016/j.soildyn.2018.01.026
4. de Sanctis, L., Maiorano, R. M. S., & Aversa, S. (2010). A method for assessing kinematic bending moments at the pile head. Earthquake Engineering & Structural Dynamics, 39(10), 1133–1154. Doi:10.1002/eqe.996
5. Deb, P., & Pal, S. K. (2021). Structural and geotechnical aspects of piled raft foundation through numerical analysis. Marine Georesources & Geotechnology, 1–24. Doi:10.1080/1064119X.2021.1943083
6. Fatahi, B., Van Nguyen, Q., Xu, R., & Sun, W. J. (2018). Three-dimensional response of neighboring buildings sitting on pile foundations to seismic pounding. International Journal of Geomechanics, 18(4). Doi:10.1061/(ASCE)GM.1943-5622.0001093
7. Ghavidel, A., Mousavi, S. R., & Rashki, M. (2018). The Effect of FEM Mesh Density on the Failure Probability Analysis of Structures. KSCE Journal of Civil Engineering, 22(7), 2371–2383. Doi:10.1007/S12205-017-1437-5
8. Hashash, Y. M. A., Musgrove, M. I., Harmon, J. A., Ilhan, O., Groholski, D. R., Philips, C. A., & Park, D. (2024). DEEPSOIL 7.0, User Manual.

9. Kampitsis, A. E., Giannakos, S., Gerolymos, N., & Sapountzakis, E. J. (2015). Soil–pile interaction considering structural yielding: Numerical modeling and experimental validation. Engineering Structures, 99, 319–333. Doi:10.1016/j.engstruct.2015.05.004
10. Kim, Y., & Jeong, S. (2011). Analysis of soil resistance on laterally loaded piles based on 3D soil-pile interaction. Computers and Geotechnics, 38(2), 248–257. Doi:10.1016/j.compgeo.2010.12.001
11. Liu, Y., Wang, X., & Zhang, M. (2015). Lateral Vibration of Pile Groups Partially Embedded in Layered Saturated Soils. International Journal of Geomechanics, 15(4). Doi:10.1061/(ASCE)GM.1943-5622.0000406
12. Luo, C., Yang, X., Zhan, C., Jin, X., & Ding, Z. (2016). Nonlinear 3D finite element analysis of soil-pile-structure interaction system subjected to horizontal earthquake excitation. Soil Dynamics and Earthquake Engineering, 84, 145–156. Doi:10.1016/j.soildyn.2016.02.005
13. Lysmer, J., & Kuhlemayer, R. J. (1969). Finite dynamic model for infinite media. Journal of Engineering Mechanics Division - Proceedings of the American Society of Civil Engineers, 95(4), 859–878.
14. Lysmer, J. (1978). Analytical Procedures in Soil Dynamics. Earthquake Engineering Research Center, University of California, Berkeley, Report No. UCB/EERC78/29.
15. Midas GTS NX. (2023). Online Manual. MIDAS Information Technology Co. MIDAS Information Technology Co.: MIDAS Information Technology Co.
16. Nateghi-A, F., & Rezaei-Tabrizi, A. (2013). Nonlinear dynamic response of tall buildings considering structure–soil–structure effects. The Structural Design of Tall and Special Buildings, 22(14), 1075–1082. Doi:10.1002/TAL.753
17. Nguyen, Q. Van, Fatahi, B., & Hokmabadi, A. S. (2016). The effects of foundation size on the seismic performance of buildings considering the soil-foundation-structure interaction. Structural Engineering and Mechanics, 58(6), 1045–1075. Doi:10.12989/sem.2016.58.6.1045
18. Nguyen, Q. Van, Fatahi, B., & Hokmabadi, A. S. (2017). Influence of size and load-bearing mechanism of piles on seismic performance of buildings considering soil-pile-structure interaction. International Journal of Geomechanics, 17(7), 1–22. Doi:10.1061/(ASCE)GM.1943-5622.0000869
19. Roth, S., Oudry, J., El-Rich, M., Shakourzadeh, H., & El, M. (2009). Influence of mesh density on a finite element model’s response under dynamic loading. Journal of Biological Physics and Chemistry, 9(4), 210–219. Doi:10.4024/39RO09C.jbpc.09.04
20. Sáez, E., Lopez-Caballero, F., & Modaressi-Farahmand-Razavi, A. (2013). Inelastic dynamic soil–structure interaction effects on moment-resisting frame buildings. Engineering Structures, 51, 166–177. Doi:10.1016/J.ENGSTRUCT.2013.01.020
21. Tabatabaiefar, S. H. R., Fatahi, B., & Samali, B. (2013). Seismic Behavior of Building Frames Considering Dynamic Soil-Structure Interaction. International Journal of Geomechanics, 13(4), 409–420. Doi:10.1061/(ASCE)GM.1943-5622.0000231
22. TBSC. (2018). Principles for the Design of Buildings Under the Impact of Earthquakes (In Turkish). Ministry of Interior, Disaster and Emergency Management Presidency, Ankara, Turkey.
23. Timurağaoğlu, M. Ö. (2024). Kinematic interaction analysis of individual soil-pile model within multi-block system. Soil Dynamics and Earthquake Engineering, 179, 108523. Doi:10.1016/j.soildyn.2024.108523
24. Timurağaoğlu, M. Ö., Fahjan, Y., & Doğangün, A. (2021). P-Y curves for laterally loaded single piles: Numerical validation. Marine Georesources & Geotechnology, 40(10), 1162-1170. Doi:10.1080/1064119X.2021.1972063
25. Wu, W., Ge, S., Yuan, Y., Ding, W., & Anastasopoulos, I. (2020). Seismic response of subway station in soft soil: Shaking table testing versus numerical analysis. Tunnelling and Underground Space Technology, 100, 103389. Doi:10.1016/j.tust.2020.103389
26. Zhang, L., & Liu, H. (2017). Seismic response of clay-pile-raft-superstructure systems subjected to far-field ground motions. Soil Dynamics and Earthquake Engineering, 101, 209–224. Doi:10.1016/j.soildyn.2017.08.004
27. Zhang, X., & Far, H. (2022). Seismic behaviour of high-rise frame-core tube structures considering dynamic soil–structure interaction. Bulletin of Earthquake Engineering, 20, 1–33. Doi:10.1007/S10518-022-01398-9