Bridge Asset Management in the 21st Century; a Case Study

Abstract

The topic of bridge asset management has taken particular relevance in the later part of the 20th Century when the advancements in the knowledge of reinforced concrete behaviour made the structural engineering community aware of the fact reinforced concrete and pre-stressed structures designed and built in the 1960’s were unlikely to last the 100 years they had been designed to. The United Kingdom, with most of its motorway network having been built during the 1960s, is a typical example of this. This paper focuses on the inspection and detailed structural assessment that Mott Macdonald’s A3M (Advanced Analysis for Asset Management) team was commissioned to undertake on this rather unique reinforced concrete arch bridge. With a total span of circa 50 m and built in 1968, this arch bridge is located in an area of outstanding natural beauty in South Wales and presently owned and managed by a Water Company. Aspects relating to the inspection and survey techniques employed, such as point cloud surveys derived from site laser scans and live load monitoring using wireless strain gauges are covered in detail in the first part of the paper. The second part of the paper focus on the aspects related to the static and dynamic modelling of the structural behaviour of the bridge using the finite element method emphasizing some of the techniques developed by the authors to establish comparisons between the experimental and numerical results. The paper finishes with a summary of the fundamental conclusions and some reflections on the future of asset management in the 21st Century.