Site-specific probabilistic load modelling for bridge reliability analysis

Colin C. Caprani, Dublin Institute of Technology
A. Belay, Trinity College Dublin
A. J. O'Connor, Trinity College Dublin

Document Type Conference Paper

In proceedings of the 3rd. International Conference on Current and Future Trends in Bridge Design, Construction and Maintenance, eds. B.I.G. Barr et al, Shanghai, China, Thomas Telford, 2003, pp.341.348


Reliability assessment of a short span beam-slab reinforced concrete bridge in Vienna is proposed using site-specific traffic data recorded using the Slovenian Weigh in Motion (SiWIM) system. An initial evaluation of the bridge using a determinintic approach shows that the critical limit state is bending. This paper describes the statistical analysis of the SiWIM data and the traffic flow simulations performed to predict the characteristic extreme load effects to which the bridge may be subjected during its remaining lifetime. These values are compared to the magnitude obtained from a deterministic approach. The influence lines used in the simulations are the real structrual response obtained from the SiWim instrumentation and the theoretical influence line for bending moment at mid-span. It is argued that reliability assessment of exising structures using actual traffic loading data is more realistic than the use of deterministic loading models.