Bridge traffic loading

Abstract

Highway infrastructure is subject to degradation over the course of its design life, just as its traffic and freight volumes increase year on year. Consequently, there is a substantial cost to society of maintaining such infrastructure. In particular, repair or replacement of existing highway bridges constitutes a large portion of national roads authorities’ maintenance budgets. Currently the in-situ strength of these bridges is assessed against highly idealised traffic loading models. Thus, the accurate estimation of bridge traffic loads has great potential for reducing the maintenance cost of highway infrastructure.

In recent years much research attention has focused on the use of probabilistic tools to model the wide variability of traffic loads that bridge structures are subject to throughout their lives. Often, such load modelling forms part of an input to an overall reliability assessment of a particular structure under study. However, traffic loading is a particularly complex phenomenon, and so requires detailed examination. For example, the critical traffic state may be free-flowing traffic with dynamic interaction of the vehicles and structure, congested traffic with associated denser traffic. The critical case will depend on the load effect of interest, the bridge length, and even the bridge construction. Further complexities include traffic growth, a lack of independence between successive vehicles and the non-identically-distributed nature of loading events caused by different vehicle arrangements. Add to this set the differences in traffic flows, flow composition and vehicle geometry across regions, and it becomes clear that the statistical models required are complex.

It is the aim of this mini-symposium to provide a single point of contact for those active in the field of bridge traffic loading research, from across the world, to meet and share their experiences and current thinking on various aspects fo the problem described.

Organizers

Colin Caprani, Dublin Institute of Technology, Ireland (colin.caprani@dit.ie)
Eugene OBrien, University College Dublin, Ireland (eugene.obrien@ucd.ie)