VicRoads manages 5100 bridges and culverts on Victorian arterial roads. All structures deteriorate under the combined effects of repeated vehicle loading and environmental factors. This paper presents an assessment of four alternative deterioration models examined under a research and development program. The most widely used model in the literature for this problem is the Markov chain model. However, the Markov chain model produces results that are counter intuitive and are not in agreement with expectations and results from theoretical modelling. Other models, for example, Weibull were examined and found to be in better agreement with expectations and results from theoretical modelling. The paper assesses these models against VicRoads bridge inspection data from Level 2 bridge inspection collected over a number of years. VicRoads introduced a regular bridge inspection program in 1996 hence the data is only available in a limited range of years. Therefore, it is essential that data alone be not used in determining the model selection, but also the prior engineering knowledge about the bridge structures is incorporated in the model selection. The paper demonstrates how it was done in this case and illustrates an alternative to the Markov chain for bridge deterioration modelling. (a) For the covering entry of this conference, please see ITRD abstract no. 0612AR242E.
Abstract