Deterioration of concrete structures in Australia under a changing climate

Concrete is the predominant construction type used in Australian critical infrastructure. Its performance, therefore, is vital for the provision of the nation's essential services and the maintenance of its economic activities. The deterioration rate of such structures depends not only on the construction processes employed and the composition of the materials used but also on the environment. A changing climate may alter this environment, especially in the longer term, causing an acceleration of deterioration processes and consequently acceleration in the decline of the safety, serviceability and durability of concrete infrastructure. An investigation of concrete carbonation-induced deterioration in the Australian city of Sydney under a changing climate is described in this paper. It is based on Monte-Carlo simulation analyses that involve three emission scenarios, i.e. AIB, AlFI and 550ppm stabilization, representing medium, high and policy-intervention GHG emission scenarios. The probabilistic analysis includes the uncertainty of climate predictions, deterioration processes, material properties, dimensions, and predictive models. Deterioration of concrete structures is represented by the probability ofreinforcement corrosion initiation and corrosion induced damage (severe cover cracking) for every calendar year between 2000 and 2100, and all of them are more or less affected by the changing climate depending on locations. The findings from the investigation provide a basis for the development of climate adaptation measures to 'climate proof' concrete structures in Australia