Reinforcement corrosion and the deflection of RC beams––an experimental critique of current test methods

This paper presents an experimental critique of the current test methods used to assess the effects of reinforcement corrosion on the serviceability deflections of reinforced concrete beams. Importantly, the work reported here highlights the weakness of tests aimed at assessing the deflection behaviour of beams in which the corrosion of the steel and the application of the service loads are undertaken as two separate and sequential processes.In the present series of tests, the central deflections of beams subjected to 23% and 34% of the design ultimate load, under 4-point loading subjected to simultaneous accelerated corrosion, were monitored over a period of approximately 30 days. Uncorroded beams were used as control samples and tested in parallel with the corroded samples.The results show the importance of assessing the structural effects of reinforcement corrosion under simultaneous load and corrosion conditions, as would occur in situ. In this situation, when 6% of the mass of steel is corroded, beam deflections are increased by 40–70% relative to the deflection of the control samples.