Study of vibration period for bridges with steel beams in Panama

Abstract

In this article the main frequency of vibration obtained in 31 spans of steel beam bridges are presented, and studied together with other 25 steel beam bridges vibration frequencies presented in previous studies. An equation that estimates the main period of vibration as a function of the span length of these bridges is presented. Additionally, matching of frequency of vibration in adjacent spans with different lengths was observed in some non-continuous-beam multi-span bridges; this phenomena is considered to be related to forced vibration in the shorter spans caused by the natural vibration of the longest spans. In addition, an equation to estimate an upper bound period of vibration as a reference to identify atypical bridges, whose vibration periods are considerably far from the trend.