Investigation of Natural Frequency for Continuous Steel Bridges with Variable Cross-sections by using Finite Element Method

Year 2018, Volume: 4 Issue: 2, 90 - 102, 27.06.2018

Hüseyin Sağlık Bilge Doran , Can Balkaya

Abstract

This paper mainly focuses
on the natural frequencies of steel I-girder continuous-span bridges with
straight haunched sections. The finite element analysis is performed to model
dynamic behaviour of bridges by using CSIBridge package. Continuous-span
bridges (two to six) with straight haunched section are considered. All the dimensions
used for generating bridge models are designed according to AASHTO LRFD
Standards. Effect of various parameters such as span length, the depth ratios
between haunched cross-section to mid-span cross-section (r), the length ratio
between haunched section to span (α),
span configuration and steel girder arrangement on natural frequencies are
investigated by numerically generating one hundred fifty three bridge models. “r”
and “α” values are set to be 0.5 -
2.0 and 0.1 - 0.5. The analysis results are given and discussed for the natural
frequency of continuous-span composite steel bridges with straight haunched
section.

Keywords

Composite steel bridges, Natural frequency, Finite element analysis, Straight haunched, Non-prismatic cross-section

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