Influence of Near-Fault Unidirectional and Bidirectional Ground Motions on DSM-Enhanced Reactor Building Foundations Considering Soil–Structure Interaction: A Case Study

Document Type : Original Article

Authors

School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran

Abstract

This study examines the seismic performance of the APR1400 nuclear reactor, focusing on soil–structure interaction (SSI) and structure–soil–structure interaction (SSSI), particularly on foundations enhanced with block deep soil mixing (DSM). The reactor, including its internal structure, containment building, and DSM layers, was modeled to evaluate its dynamic response to unidirectional and bidirectional near-fault ground motions with different frequency contents. Results indicate that the internal structure experiences higher horizontal accelerations than the containment building, while rocking-induced vertical accelerations are significant in the containment. DSM effectiveness depends on the frequency content of the ground motion, soil properties, and DSM depth. Horizontal accelerations are largely unaffected at high frequencies, but low-frequency responses are notably reduced. In the vertical component, accelerations in the 2–10 Hz range increase by over 140% in the containment building and nearly 60% in the internal structure for an 18-m DSM layer, highlighting the vulnerability of many reactor components. Morlet wavelet analysis shows that DSM reduces horizontal-acceleration energy transmitted to the containment building while shifting it to higher frequencies. In contrast, vertical-acceleration energy is substantially amplified, particularly in the 3–7 Hz range. SSSI effects significantly influence structural response: for modeling a second reactor at a 30-m distance, horizontal energy decreases by approximately 34% in the internal structure, while vertical acceleration energy increases by 3.2 times; at 70-m spacing, vertical energy rises by up to 8 times. Bidirectional near-fault excitations further increase vertical accelerations by 6–46 times compared to unidirectional loading, depending on the structure and earthquake. These findings underscore the critical importance of accounting for multidirectional excitations, DSM-induced effects, and SSSI in the seismic design of nuclear facilities, particularly for sensitive equipment and high-frequency structural responses. Accurate evaluation of these factors is essential to ensure operational safety and prevent potential damage to reactor components under severe near-fault ground motions.

Keywords

Main Subjects

References

  1. Islam, M. R., Turja, S. D., Van Nguyen, D., Forcellini, D., Kim, D. Seismic soil-structure interaction in nuclear power plants: An extensive review. Results in Engineering, 2024; 23: 102694. doi:10.1016/j.rineng.2024.102694.
  2. Dezhkam, B., Yaghfoori, A. Soil foundation effect on the vibration response of concrete foundations using mathematical model. Computers and Concrete, 2018; 22: 221-225. doi:10.12989/cac.2018.22.2.221.
  3. Kitada, Y., Hirotani, T., Iguchi, M. Models test on dynamic structure–structure interaction of nuclear power plant buildings. Nuclear Engineering and Design, 1999; 192: 205-216. doi:10.1016/S0029-5493(99)00109-0.
  4. Yano, T., Kitada, Y., Iguchi, M., Hirotani, T., Yoshida, K. Model test on dynamic cross interaction of adjacent buildings in nuclear power plants. In: 12th world conference on earthquake engineering; 2000 30 Jan-4 Feb; Auckland, New Zealand. p. 1-8.
  5. Yano, T., Naito, Y., Iwamoto, K., Kitada, Y., Iguchi, M. Model Test on Dynamic Cross Interaction of Adjacent Building Nuclear Power Plants - Overall Evaluation on Field Test. In: Transactions of the 17th International Conference on Structural Mechanics in Reactor Technology (SMiRT 17); 2003 Aug 17–22; Prague, Czech Republic. p. 1-8.
  6. Clouteau, D., Broc, D., Devésa, G., Guyonvarh, V., Massin, P. Calculation methods of Structure–Soil–Structure Interaction (3SI) for embedded buildings: Application to NUPEC tests. Soil Dynamics and Earthquake Engineering, 2012; 32: 129-142. doi:10.1016/j.soildyn.2011.08.005.
  7. Roy, C., Bolourchi, S., Eggers, D. Significance of structure–soil–structure interaction for closely spaced structures. Nuclear Engineering and Design, 2015; 295: 680-687. doi:10.1016/j.nucengdes.2015.07.067.
  8. Lee, T. H., Wesley, D. A. Soil-structure interaction of nuclear reactor structures considering through-soil coupling between adjacent structures. Nuclear Engineering and Design, 1973; 24: 374-387. doi:10.1016/0029-5493(73)90007-1.
  9. Bolisetti, C., Whittaker, A. Seismic structure–soil–structure interaction in nuclear power plant structures. In: 21st International Conference on Structural Mechanics in Reactor Technology (SMiRT 21); 2011 Nov 6-11; New Delhi, India. p. 6-11.
  10. Yue, D., Ghiocel, D. M., Fuyama, H., Ogata, T., Stark, G. Structure-soil-structure interaction effects for two heavy NPP buildings with large-size embedded foundations. In: 22nd International Conference on Structural Mechanics in Reactor Technology (SMiRT22); 2013 Aug 18-23; San Francisco, California. p. 18-23.
  11. Anderson, L. M., Carey, S., Amin, J. Effect of Structure, Soil, and Ground Motion Parameters on Structure-Soil-Structure Interaction of Large Scale Nuclear Structures. Structures Congress, 2012; 2862-2873. doi:10.1061/41171(401)249.
  12. Kanellopoulos, C., Rangelow, P., Jeremic, B., Anastasopoulos, I., Stojadinovic, B. Dynamic structure-soil-structure interaction for nuclear power plants. Soil Dynamics and Earthquake Engineering, 2024; 181: 108631. doi:10.1016/j.soildyn.2024.108631.
  13. Shaghaghi, M. M., Kani, I. M., Yousefi, H. The Seismic Behavior of Block Type Deep Soil Mixing. Latin American Journal of Solids and Structures, 2021; 18: 1-17. doi:10.1590/1679-78256439.
  14. Yaghfoori, A., Mahmoudzadeh Kani, I., Yousefi, H. Seismic performance and optimization of deep soil mixing (DSM) for response mitigation at power plant sites. Engineering Computations, 2025; 1-42. doi:10.1108/EC-05-2025-0508.
  15. Van Nguyen, D., Kim, D., Duy Nguyen, D. Nonlinear seismic soil-structure interaction analysis of nuclear reactor building considering the effect of earthquake frequency content. Structures, 2020; 26: 901-914. doi:10.1016/j.istruc.2020.05.013.
  16. Bolisetti, C., Whittaker, A. S., Coleman, J. L. Linear and nonlinear soil-structure interaction analysis of buildings and safety-related nuclear structures. Soil Dynamics and Earthquake Engineering, 2018; 107: 218-233. doi:10.1016/j.soildyn.2018.01.026.
  17. (ASCE), A. S. o. C. E. Seismic analysis of safety-related nuclear structures. 1st ed. Reston (VA): American Society of Civil Engineers (ASCE); 2017. doi:10.1061/9780784413937.
  18. Jeremić, B., Jie, G., Preisig, M., Tafazzoli, N. Time domain simulation of soil–foundation–structure interaction in non‐uniform soils. Earthquake Engineering & Structural Dynamics, 2009; 38: 699-718. doi:10.1002/eqe.896.
  19. Amalu, P. A., Jayalekshmi, B. R. Study on seismic response of unconnected piled raft with rubber mixed soil. Materials Today: Proceedings, 2023; doi:10.1016/j.matpr.2023.10.018.
  20. Çetindemir, O., Zülfikar, A. C. Numerical validation of fully coupled nonlinear seismic soil–pile–structure interaction. Buildings, 2024; 14: 1502. doi:10.3390/buildings14061502.
  21. Cruz, L., Todorovska, M. I., Chen, M., Trifunac, M. D., Aihemaiti, A., Lin, G., Cui, J. The role of the foundation flexibility on the seismic response of a modern tall building: Vertically incident plane waves. Soil Dynamics and Earthquake Engineering, 2024; 184: 108819. doi:10.1016/j.soildyn.2024.108819.
  22. Nielsen, A. H. Absorbing boundary conditions for seismic analysis in ABAQUS. In: ABAQUS users’ conference; 2006 May 23-25; Cambridge, Massachusetts. p. 359-376.
  23. Rathje, E. M., Faraj, F., Russell, S., Bray, J. D. Empirical relationships for frequency content parameters of earthquake ground motions. Earthquake Spectra, 2004; 20: 119-144. doi:10.1193/1.1643356.
  24. Tso, W. K., Zhu, T. J., Heidebrecht, A. C. Engineering implication of ground motion A/V ratio. Soil Dynamics and Earthquake Engineering, 1992; 11: 133-144. doi:10.1016/0267-7261(92)90027-B.
  25. Patrício, J. D., Gusmão, A. D., Ferreira, S. R. M., Silva, F. A. N., Kafshgarkolaei, H. J., Azevedo, A. C., Delgado, J. M. P. Q. Settlement Analysis of Concrete-Walled Buildings Using Soil–Structure Interactions and Finite Element Modeling. Buildings, 2024; 14: 746. doi:10.3390/buildings14030746.
  26. Uzun, S., Ayvaz, Y. Implementation of PMDL and DRM in OpenSees for Soil-Structure Interaction Analysis. Applied Sciences, 2024; 14: 8519. doi:10.3390/app14188519.
  27. Towhata, I. Geotechnical earthquake engineering: Damage mechanism observed. 1st ed. Berlin (DE): Springer International Publishing;; 2015. doi:10.1007/978-3-642-35344-4_2.
  28. Yaghfoori, A., Mahmoudzadeh Kani, I., Yousefi, H. Seismic behavior of dry sandy soils improved with Block-Type Deep Soil Mixing in near-fault regions. AUT Journal of Civil Engineering, 2025; doi:10.22060/ajce.2025.24157.5923.
  29. Asgari, A., Ranjbar, F., Bagheri, M. Seismic resilience of pile groups to lateral spreading in liquefiable soils: 3D parallel finite element modeling. Structures, 2025; 74: 108578. doi:10.1016/j.istruc.2025.108578.
  30. Asgari, A., Sorkhi, S. F. A. Wind turbine performance under multi-hazard loads: Wave, wind, and earthquake effects on liquefiable soil. Results in Engineering, 2025; 26: 104647. doi:10.1016/j.rineng.2025.104647.
  31. Chopra, A. K., Chintanapakdee, C. Comparing response of SDF systems to near‐fault and far‐fault earthquake motions in the context of spectral regions. Earthquake Engineering & Structural Dynamics, 2001; 30: 1769-1789. doi:10.1002/eqe.92.
  32. Bozorgnia, Y., Campbell, K. W. The vertical-to-horizontal response spectral ratio and tentative procedures for developing simplified V/H and vertical design spectra. Journal of Earthquake Engineering, 2004; 8: 175-207. doi:10.1080/13632460409350486.
  33. Tyapin, A. Effect of soil improvement on seismic response. In: 24th International Conference on Structural Mechanics in Reactor Technology (SMiRT 24 ); 2017 Aug 20-25; Busan, Korea. p. 1-10.
  34. Lu, X., Jing, L., Ma, Y., Yang, J., Qi, W. Shaking table test for seismic response of nuclear power plant on non-rock site. Sustainability, 2023; 15: 10366. doi:10.3390/su151310366.
  35. Anagnostopoulos, S. A., Spiliopoulos, K. V. An investigation of earthquake induced pounding between adjacent buildings. Earthquake Engineering & Structural Dynamics, 1992; 21: 289-302. doi:10.1002/eqe.4290210402.
  36. Nguyen, D.-D., Thusa, B., Park, H., Azad, M. S., Lee, T.-H. Efficiency of various structural modeling schemes on evaluating seismic performance and fragility of APR1400 containment building. Nuclear Engineering and Technology, 2021; 53: 2696-2707. doi:10.1016/j.net.2021.02.006.
  37. Lee, J. H. Practical Numerical Approach for Nonlinear Soil-Structure Interaction Analysis of a NPP Containment Building. In: Transactions of the Korean Nuclear Society Spring Meeting; 2018 May 17-18; Jeju, Korea. p. 1-2.
  38. Kabanda, J., Kwon, O.-S., Kwon, G. Time and frequency domain analyses of the Hualien Large-Scale Seismic Test. Nuclear Engineering and Design, 2015; 295: 261-275. doi:10.1016/j.nucengdes.2015.10.011.
  39. Asgari, A. Effect of Deep Soil Mixing Grid on the Reduction Coefficient in the Liquefiable Soil: 3D Nonlinear Modeling. Journal of Civil and Environmental Engineering, 2025; 55: 89-98. doi:10.22034/ceej.2025.63522.2381.
  40. Sextos, A. G., Manolis, G. D., Athanasiou, A., Ioannidis, N. Seismically induced uplift effects on nuclear power plants. Part 1: Containment building rocking spectra. Nuclear Engineering and Design, 2017; 318: 276-287. doi:10.1016/j.nucengdes.2016.12.035.
  41. Saxena, N., Paul, D., Kumar, R. Effects of slip and separation on seismic SSI response of nuclear reactor building. Nuclear Engineering and Design, 2011; 241: 12-17. doi:10.1016/j.nucengdes.2010.10.011.
  42. Saxena, N., Paul, D. K. Effects of embedment including slip and separation on seismic SSI response of a nuclear reactor building. Nuclear Engineering and Design, 2012; 247: 23-33. doi:10.1016/j.nucengdes.2012.02.010.
Civil Engineering and Applied Solutions
Volume 2, Issue 3
July 2026
Pages 49-72

Files

History

  • Receive Date: 13 December 2025
  • Revise Date: 06 January 2026
  • Accept Date: 31 January 2026
  • First Publish Date: 31 January 2026

Share

How to cite

Statistics