Gholamreza Ghodrati Amiri - ۱Professor, Iran university of science and Technology
Alireza Tajik Davoudi - Gragduate student, Iran university of science and Technology
Mohammad Mahdi Memarpour - Gragduate student, Iran university of science and Technology
Masoud Akbarzadeh - ۴Gragduate student, Iran university of science and Technology

Strong earthquakes of the past decade have revealed destructive effects of motions in vicinity of faults. 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 (1997): International Conference of Building Officials, Structural Design Provisions (UBC97) and European Standard (2001): Design of Structures for Earthquake Resistance (Eurocode 8) spectra in 2 levels. In addition, the ratio of vertical to horizontal spectra has been computed and compared with the assumed value of 2/3 in some code provisions.

horizontal spectrum; vertical spectrum; nearfield; forward directivity effect; filing step; UBC97;Eurocode 8; bridge