Non-Uniform Relationship for Soil-Foundation Reaction

نوع مقاله : مقاله پژوهشی

نویسندگان

1 Ph.D. Candidate, School of Civil Engineering, University of Tehran, Tehran, Iran Email:hajian.m@ut.ac.ir

2 Professor, School of Civil Engineering, University of Tehran, Tehran, Iran

10.22034/cpj.2022.349082.1145

چکیده

This paper presents an exact formula for considering soil stiffness under the foundation. This formula derived from a 3D modeling of eight strip footings with different foundation widths supported on a soil medium. In the case of an earthquake, the behavior of the substructure soil plays an important role in the response of the structure. Studies show that the dynamic response spectrum of a structure on a flexible foundation is different from the response spectrum of a structure on a rigid foundation. Hence it is important to model the soil medium correctly to reach the best seismic results. There are different methods for modeling soil-structure interaction. These models use a constant value for modeling the soil stiffness. However, the soil stiffness varies along the foundation and should be calculated by analytical studies. This paper provides a simple formula which shows a non-uniform soil stiffness under the strip foundation and can be used for practical purposes.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Non-Uniform Relationship for Soil-Foundation Reaction

نویسندگان [English]

  • Morvarid Hajian 1
  • Reza Attarnejad 2
1 Ph.D. Candidate, School of Civil Engineering, University of Tehran, Tehran, Iran Email:hajian.m@ut.ac.ir
2 Professor, School of Civil Engineering, University of Tehran, Tehran, Iran
چکیده [English]

This paper presents an exact formula for considering soil stiffness under the foundation. This formula derived from a 3D modeling of eight strip footings with different foundation widths supported on a soil medium. In the case of an earthquake, the behavior of the substructure soil plays an important role in the response of the structure. Studies show that the dynamic response spectrum of a structure on a flexible foundation is different from the response spectrum of a structure on a rigid foundation. Hence it is important to model the soil medium correctly to reach the best seismic results. There are different methods for modeling soil-structure interaction. These models use a constant value for modeling the soil stiffness. However, the soil stiffness varies along the foundation and should be calculated by analytical studies. This paper provides a simple formula which shows a non-uniform soil stiffness under the strip foundation and can be used for practical purposes.

کلیدواژه‌ها [English]

  • Soil stiffness
  • Soil-structure interaction
  • Winkler method
  • Flexible foundation
  • Modeling soil-structure interaction
Aron, C., and Jonas, E., 2012. “Structural element approaches for soil-structure interaction”. Structural Engineering and Building Performance Design, Chalmers University of Technology. Master of Science.
Chen, Z., Hutchinson, T.C. and Raychowdhury, P., 2010. “Effects of foundation configuration variation on seismic response of moment-frame buildings”. In Structures Congress 2010: 19th Analysis and Computation Specialty Conference (pp. 105-116).
Coşkun, I., 2000. “Non-linear vibrations of a beam resting on a tensionless Winkler foundation”. Journal of Sound and Vibration, 236(3), pp.401-411.
Gazetas, G. and Mylonakis, G. 1998 “Seismic soil-structure interaction: new evidence and emerging issues”. Geotechnical Earthquake Engineering and Soil Dynamics III
Gazetas, G., 1991. “Formulas and charts for impedances of surface and embedded foundations”. Journal of geotechnical engineering, 117(9), pp.1363-1381.
Ghannad, M.A. and Jahankhah, H., 2004. “Strength reduction factors considering soil-structure interaction”. In Proceedings of the 13th World conference on earthquake engineering, June.
Hetényi, M., 1946. Beam on Elastic Foundation. The University of Michigan Press, Ann Arbor
Hokmabadi, A.S., Fatahi, B. and Samali, B., 2014. “Physical modeling of seismic soil-pile-structure interaction for buildings on soft soils”. International Journal of Geomechanics, 15(2), p.04014046.   
Hokmabadi, A.S., Fatahi, B. and Samali, B., 2014. “Physical modeling of seismic soil-pile-structure interaction for buildings on soft soils”. International Journal of Geomechanics, 15(2), p.04014046.   
Hosseinzadeh, N.A., Nateghi-Alahi, F. and Behnamfar, F., 2004. “Shake Table Study of Soil-Structure Interaction Effects on Seismic Response of Adjacent Buildings”. Journal of Advanced Materials in Engineering (Esteghlal), 22(2), pp.51-71.
Kanwal, F., 2017. Evaluation of Response Modification Factor in Consideration of Soil-Structure Interaction, Master Thesis.  
Kim, Y.S. and Roesset, J.M., 2004. “Effect of nonlinear soil behavior on inelastic seismic response of a structure”. International Journal of Geomechanics, 4(2), pp.104-114.
Kramer, S. L. (1996). Geotechnical earthquake engineering, Prentice Hall, Upper Saddle River, NJ.
Li, M., Lu, X., Lu, X. and Ye, L., 2014. “Influence of soil–structure interaction on seismic collapse resistance of super-tall buildings”. Journal of Rock Mechanics and Geotechnical Engineering, 6(5), pp.477-485.
Ma, X.H., Cheng, Y.M., Au, S.K., Cai, Y.Q. and Xu, C.J., 2009. “Rocking vibration of a rigid strip footing on saturated soil.” Computers and Geotechnics, 36(6), pp.928-933.
Mylonakis, G. and Gazetas, G., 2000. “Seismic soil-structure interaction: beneficial or detrimental?”. Journal of Earthquake Engineering, 4(3), pp.277-301.
Mylonakis, G., 2001. “Winkler modulus for axially loaded piles”. Geotechnique, 51(5), pp.455-462
National Institute of Standards and Technology (NIST), 2012. Soil-Structure Interaction for Building Structures, GCR 12-917-21, Gaithersburg, Maryland.
Nguyen, Q.V., 2017. Effects of foundation characteristics and building separation gap on seismic performance of mid-rise structures incorporating soil-foundation-structure-interaction (Doctoral dissertation). 
Raheem, S.E.A., Ahmed, M.M. and Alazrak, T.M., 2015. Evaluation of soil–foundation–structure interaction effects on seismic response demands of multi-story MRF buildings on raft foundations. International Journal of Advanced Structural Engineering (IJASE), 7(1), pp.11-30.
Stewart, J.P., Fenves, G.L. and Seed, R.B., 1999a. “Seismic soil-structure interaction in buildings. I: Analytical methods”. Journal of Geotechnical and Geoenvironmental Engineering, 125(1), pp.26-37.            
Stewart, J.P., Seed, R.B. and Fenves, G.L., 1998. “Empirical evaluation of inertial soil-structure interaction effects”. University of California, Berkeley, CA: Pacific Earthquake Engineering Research Center.
Tabatabaiefar, H. R., Fatahi, B. and Samali, B., 2013. “Lateral seismic response of building frames considering dynamic soil-structure interaction effects”. Structural Engineering and Mechanics, 45(3), pp.311-321.     
Tabatabaiefar, S.H.R., 2012. Determining seismic response of mid-rise building frames considering dynamic soil-structure interaction, Doctoral dissertation.
Tahghighi, H. and Rabiee, M., 2015. “Nonlinear Soil-Structure Interaction Effects on Building Frames: A Discussion on the Seismic Codes”. Journal of Seismology and Earthquake Engineering, 17(2), pp.141-151. 
Teodoru, I.B., 2009. “Beams on elastic foundation the simplified continuum approach”. Buletinul Institutului Politehnic din lasi. Sectia Constructii, Arhitectura, 55(4), p.37.
Torabi, H. and Rayhani, M.T., 2014. “Three dimensional finite element modeling of seismic soil–structure interaction in soft soil”. Computers and Geotechnics, 60, pp.9-19.  
University).
Veletsos, A.S. and Prasad, A.M., 1989. “Seismic interaction of structures and soils: stochastic approach”. Journal of Structural Engineering, 115(4), pp.935-956.
Wang, Y.H., Tham, L.G. and Cheung, Y.K., 2005. “Beams and plates on elastic foundations: a review”. Progress in Structural Engineering and Materials, 7(4), pp.174-182.
Winkler, E., 1867. Die Lehre von der Elasticitaet und Festigkeit: mit besonderer Rücksicht auf ihre Anwendung in der Technik für polytechnische Schulen, Bauakademien, Ingenieue, Maschinenbauer, Architecten, etc (Vol. 1). Dominicus