Document Type : Research Paper


Civil Engineering Dept., University of Technology-Iraq, Alsina’a street, 10066 Baghdad, Iraq.


Seismic activity has emerged as a mostly attractive issue for researchers and engineers, particularly in light of the recent occurrence of severe earthquakes worldwide, such as those felt in Turkey and Syria. Most entities prone to seismic damage are the structures. Any type of structure consists of a composite system involving structure, foundation, and soil. Previously, numerical and analytical methods for dynamic seismic analysis of structures ignored the impact of this system during earthquakes. In other words, soil-structure interaction (SSI) was ignored. Moreover, another important factor that was not considered is the interaction between structures and soil, or what is called structure-soil-structure interaction (SSSI), which usually occurs between two adjacent structures. This research aims to comprehensively understand the SSSI by performing a series of dynamic tests using a shaking table system. The tests concentrate on the effect of height on the dynamic behavior between two adjacent steel structures rested on sand soil. This study employed four novel small-scale multi-degree-of-freedom steel structure models: three, four, and five-story steel structures against a three-story steel structure. The results indicated that the tallest building had the maximum effect on the shorter one, especially on the top displacement with a peak value of 3.82 cm, top acceleration with a peak value of about 0.2 g, and foundation rotation with a peak value of around 1 degree. However, the effect of the structure height has a reverse impact on the soil pressure beneath the foundation of the shortest structure since the largest pressure response was recorded for the effect of the shortest similar adjacent building with a peak value of 8.8 kPa. In comparison, the highest building has the lowest effect on the shortest building, with a peak value of 6 kPa. 

Graphical Abstract


  • Seismic tests consisted of three small-scale structural steel models of varying heights on sand soil.
  • Structural seismic responses were represented by time-domain behaviors like acceleration and displacement.
  • Taller buildings strongly affected shorter adjacent buildings' acceleration and displacement.
  • Taller buildings weakly affected the soil pressure of adjacent shorter buildings.


Main Subjects

  1. Y. Fattah, M. J. Hamood, S. H. Dawood, Dynamic Analysis of Soil-Structure Interaction Problems Considering Infinite Boundaries, J. Eng. Technol., 26 (2008) 725-746.
  2. Y. Fattah, M. J. Hamood, S. H. Dawood, The Response of Tunnels to Earthquake Excitations, 7th European Conference on Structural Dynamics (EURODYN 2008), at the Institute of Sound and Vibration Research University of Southampton.
  3. Hosseinzadeh, N.A. and Nateghi12-A, F. (2004). Shake table study of soil structure interaction effects on seismic response of single and adjacent buildings. 13th World Conference on Earthquake Engineering Vancouver, B.C., Canada August 1-6. Paper No. 1918.
  4. Aldaikh, N. A. Alexander, E. Ibraim, J. Knappett, Shake table testing of the dynamic interaction between two and three adjacent buildings (SSSI), Soil Dyn. Earthq. Eng., 89 (2016) 219–32.
  5. Jabary RN, Madabhushi SPG, Structure-soil-structure interaction effects on structures retrofitted with tuned mass dampers, Soil Dyn. Earthq. Eng., 100 (2017) 301–15.
  6. Kirkwood, S. A. Dashti, Centrifuge Study of Seismic Structure-Soil-Structure Interaction on Liquefiable Ground and Implications for Design in Dense Urban Areas, Earthq. Spectra, 34 (2018)1113–34.
  7. Barrios, V. Nanayakkara, P. De Alwis, N. Chouw, Effects of Slenderness and Fundamental Frequency on the Dynamic Response of Adjacent Structures, Int. J. Struct. Stab. Dyn., 19 (2019).
  8. L. Ngo, J. Kim, S. H. Chang and C. Lee, Effect of height ratio and mass ratio on structure—soil—structure interaction of two structures using centrifugal experiment, Appl. Sci.,  9 (2019) 526.
  9. He, and N. Jiang, Substructure shake table test for equipment-adjacent structure–soil interaction based on the branch mode method, Struct. Design Tall Spec. Build., 28 (2019) 1-19.
  10. Behnamfar, F. and Sugimura, Y., Response analysis of adjacent structures and comparison with recorded data, 12 WCEE, 2308, 2000.
  11. Yahyai, M. Mirtaheri, M. Mahoutian, A. S. Daryan and M. A. Assareh, Soil structure interaction between two adjacent buildings under earthquake load, Am. J. Eng. Appl. Sci., 2008 (2008)121–5.
  12. Naserkhaki and H. Pourmohammad, SSI and SSSI effects in seismic analysis of twin buildings: Discrete model concept. J. Civil Eng. Manage., 18 (2012) 890- 898.
  13. A. Farghaly, Seismic analysis of 3-D two adjacent buildings connected by viscous dampers with effect of underneath different, soil kinds, Smart. Struct. Syst., 15 (2015) 1293–309.
  14. Wang H-F. Structure-Soil-Structure Interaction between Underground Structure and Surface Structure. In: Svalova V, editor, Earthquakes - Forecast, Prognosis and Earthquake Resistant Construction. In Tech, (2018).
  15. Bybordiani and Y. S. Arici, Structure-soil-structure interaction of adjacent buildings subjected to seismic loading, Earthq. Eng. Struct Dyn., 48 (2019) 731-748.
  16. Ada and Y. Ayvaz, The structure-soil-structure interaction effects on the response of the neighbouring frame structures. Latin Am. J. Solids Struct., 16 (2019).
  17. Gan, P. Li, Q. Liu, Study on Dynamic structure-soil-structure interaction of three adjacent tall buildings subjected to seismic loading, Sustainability, 12 (2020) 336.
  18. Kumar, S.S. Mishra, Dynamic response of buildings on different types of foundations through shake table tests considering SSI effect, Int. J. Civil Eng. Technol., 9 (2018) 205–16.