Comfort related design of railway bridges

Abstract

Arie Romeijn, born 1958. PhD on Stress and Strain Concentration Factors of Welded Multiplanar Tubular Joints. Specialist in the field of bridges, offshore structures and fatigue. SummaryThe most uncomfortable vibrations for train passengers occur at vertical track irregularities like bridges and transitions. The Eurocode limits the vibration level by prescribing minimum bridge stiffness. However, the theoretical background of these limits is not clear. The scope of this study is to give a review on these stiffness limits based on a probabilistic approach. This approach uses a renewed comfort model for the relation between comfort and vertical vibrations, and a state of the art dynamic model for the relation between vibrations and bridge stiffness. Based on this probabilistic approach, a case has been studied in which the minimum stiffness for a bridge like the Moerdijk Bridge has been calculated. The results differ significantly from the Eurocode: according to the probabilistic approach a bridge may be a factor 1.8 less stiff than prescribed. Should the Eurocode be reviewed?