Characteristics of Horizontal and Vertical Near-Field Ground Motions and Investigation of Their Effects on the Dynamic Response of Bridges

Document Type : Regular Paper


1 Civil Engineering Department, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran

2 Center of Excellence for Fundamental Studies in Structural Engineering, College of Civil Engineering, Iran University of Science and Technology, Narmak, Tehran, Iran


Recently, concerning failure of structures due to earthquakes, special investigations of near fault ground motions have been noticed. Hence, in this paper, characteristics of near field ground motions have been considered in horizontal and vertical directions. In this consideration, the record averages have been compared with Uniform Building Code and Eurocode8 spectra in two levels. In addition, the ratio of vertical to horizontal spectra has been computed and compared with the assumed value of two thirds in some code provisions. Finally, the response of near field records on five artificial bridges that have covered all 0.5-2.5 seconds periods, have been investigated for comparing the ratio of responses in near field to far field, and forward to backward directivity effects. In addition, the results of the response spectrum analyses of six different bridges subjected to vertical excitations are presented.


Main Subjects

[1] Abrahamson, N. (2001). “Incorporating Effects of Near Fault Tectonic Deformation into Design Ground Motions”, a presentation sponsored by the Earthquake Engineering Research Institute  Visiting Professional Program, hosted by State University of New York  at Buffalo, 26 Oct. 2001. Available at
[2] Ambarseyes, N. N., Douglas, J. (2000). “Reappraisal of the Effect of Vertical Ground Motions on Response”. Engineering Seismology and Earthquake Engineering, ESEE, Report No. 00-4, Department of Civil Engineering and Environmental Engineering, Imperial College of Science, Technology and Medicine.
[3] Ambarseyes, N. N., Simpson, K. A. (1996). “Prediction of vertical response spectra in Europe”. Earthquake Engineering & Structural Dynamics, Vol. 25(4), pp. 401-412.
[4] American Association of State Highway & Transportation Officials (AASHTO), (1992). Standard specifications for highway bridges,
[5] Boore, D. M., Joyner, W. B. and Fumal, T. E. (1997). “Equations for estimating horizontal response spectra and peak acceleration from western North American earthquakes: A summary of recent work”. Seismological Research Letters, Vol. 68(1), pp. 128-153. 
[6] Bozorgnia, Y. Niazi, M. (1993). “Distance scaling of vertical and horizontal response spectra of the Loma Prieta earthquake”, Earthquake Engineering & Structural Dynamics, Vol. 22(8), pp. 695-707.
[7] Bozorgnia, Y., Niazi, M., Campbell, K. W. (1995). “Characteristic of free-field vertical ground motion during the Northridge earthquake”. Earthquake Spectra, Vol. 11(4), pp. 515-525.
[8] Elgamal, A., He, L. (2004). “Vertical earthquake ground motion records: An overview”. Journal of Earthquake Engineering, Vol. 5(8), pp. 663-697.
[9] European Standard (2001), Eurocode 8: Design of Structures for Earthquake Resistance, DRAFT No 4, Final Project Team Draft (Stage 34), prEN 1998-1: 200X, 1-19.
[10] Foutch, A. D., (1997). “A note on the occurrence and effects of vertical earthquake ground motion,” Proceedings of the FHWA/NCEER Workshop on the National Representation of Seismic Ground Motion for New and Existing Highway Facilities, Technical Report NCEER-97-0010.
[11] Frankel, A. D., Meuller, C., Barnhard, T., Leyendecker, E., Wesson, R., Harmsen, A., Klein, F., Perkins, D., Dickman, N., Hanson, S., (2000). “USGS national seismic hazard maps”. Earthquake Spectra, Vol. 16(1), pp. 1-19.
[12] Hall, J. F., Heaton, T. H., Halling, M. W., and Wald, D. J., (1995). “Near-source ground motions and effects on flexible buildings”. Earthquake Spectra, Vol. 11(4), pp. 569-605.
[13] Heaton, T. H., Hall, J. F., Wald, D. J., Halling, M. W. (1995). “Response of high-rise and base-isolated buildings to a hypothetical Mw 7.0 blind thrust earthquake”. Science, Vol. 267 (13), pp. 206-211.
[14] Kircher, C.A. (2003). “Development of Seismic Design Criteria for Building Codes”. Kircher & Associates, Palo Alto, CA.
[15] Kalkan, E., Adalier, K., Pamuk, A., (2004). “Near field effects and engineering implications of recent earthquakes in Turkey”. Proceedings, 5th International Conference on Case Histories in Geotechnical Engineering, New York, NY, April 13-17, Paper No. 3-30.
[16] Mavroeidis, G. P., and Papageorgiou, A. S., (2003). “A mathematical expression of Near-fault ground motions”. Bull. Seismol. Soc. Am. 93 (3), pp. 1099-1131.
[17] Memarpour, M.M. (2005). “Investigation of failure reasons of bridges in recent earthquakes.” M.Sc. Thesis, Dept of Civil Engineering, Iran University of Science and Technology, Tehran, Iran. (in Farsi)
[18] Newmark, N. M., Blume J. A., Kapur K. K., (1973). “Seismic design spectra for nuclear power plants”. Journal of the Power Division, Vol.99, pp. 287-303.
[19] Pacific Earthquake Engineering Strong-Motion Databases. Available at:
[20] Priestly, MJ. N., Seible, F., Calvi G. M., (1996). “Seismic Design and Retrofit of Bridges”. John Wiley and Sons, Inc., New York.
[21] SAP 2000. Integrated Finite Element Analysis and Design of Structures, Version Advanced 10.01, 2005.
[22] SeismoSignal. SeismoSoft, Version 3.1.0, 2006.
[23] Silva, W. J. (1997). “Characteristics of vertical ground motions for applications to engineering design” Proceedings of the FHWA/NCEER Workshop on the National Representation of Seismic Ground Motion for New and Existing Highway Facilities, Technical Report NCEER-97-0010.
[24] Somerville, P. G., (1998). ”Development of an improved representation of near-fault ground motions” SMIP98, Proceedings, Seminar on Utilization of Strong-Motion Data, Oakland, CA, Sept. 15, California Division of Mines and Geology, Sacramento, CA, pp. 1-20.
[25] Somerville, P. G., Smith, N., Graves, R., Abrahamson, N., (1997). ”Modification of empirical strong motion attenuation relations to include the amplitude and duration effects of rupture directivity”. Seismol, Res. Lett. Vol. 68, pp. 180-203.
[26] Uniform Building Code (UBC). (1997) International Conference of Building Officials, Structural Design Provisions.
[27] United States Geological Survey (USGS).